criyle/codenet-compile-errors huggingface dataset:
Language: C

#include <stdio.h>

int main(){
	
	int m[1000],f[1000],r[1000];
	
	int i=0;
	
	while(1){
		
		if(i!=0)
		
			scanf("%*c");
		
		scanf("%d %d %d",&m[i],&f[i],&r[i]);
		
		if(m[i]==-1&&f[i]==-1&&r[i]==-1)
			
			break;
		
	}

	int t;
	
	for(t=0;t<=i-1;t++){
		
		
		if(m[t]==-1||[t]==-1){
			
			printf("F\n");
			
		}
		
		else if(m[t]+f[t]>=80){
			
			printf("A\n");
			
		}
		
		else if(m[t]+f[t]>=65){
			
			printf("B\n");
			
		}
		
		else if(m[t]+f[t]>=50){
			
			printf("C\n");
			
		}
		
		else if(m[t]+f[t]>=30&&r[t]>=50){
			
			printf("C\n");
			
		}
		
		else if(m[t]+f[t]>=30){
			
			printf("D\n");
			
		}
		
		else{
			
			printf("F\n");
			
		}
		
	}
	
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:28:30: error: expected expression before '[' token
   28 |                 if(m[t]==-1||[t]==-1){
      |                              ^
Language: C

#include <stdio.h>

int main(){
	
	int m[1000],f[1000],r[1000];
	
	int i=0;
	
	while(1){
		
		if(i!=0)
		
			scanf("%*c");
		
		scanf("%d %d %d",&m[i],&f[i],&r[i]);
		
		if(m[i]==-1&&f[i]==-1&&r[i]==-1)
			
			break;

i++;
		
	}

	int t;
	
	for(t=0;t<=i-1;t++){
		
		
		if(m[t]==-1||[t]==-1){
			
			printf("F\n");
			
		}
		
		else if(m[t]+f[t]>=80){
			
			printf("A\n");
			
		}
		
		else if(m[t]+f[t]>=65){
			
			printf("B\n");
			
		}
		
		else if(m[t]+f[t]>=50){
			
			printf("C\n");
			
		}
		
		else if(m[t]+f[t]>=30&&r[t]>=50){
			
			printf("C\n");
			
		}
		
		else if(m[t]+f[t]>=30){
			
			printf("D\n");
			
		}
		
		else{
			
			printf("F\n");
			
		}
		
	}
	
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:30:30: error: expected expression before '[' token
   30 |                 if(m[t]==-1||[t]==-1){
      |                              ^
Language: C

#include<stdio.h>

int main(void)
{
	int m;
	int f;
	int r;
	
	while(1){
		scanf("%d %d %d", &m, &f, &r);
		
		if(m == -1 && f == -1 && r == -1){
			break;
		}
		if(m + f >= 80){
			printf("A");
		}
		else if(m + f >= 65 && m + f < 80){
			printf("B");
		}
		else if((m + f >= 50 && m + f < 65)|| (r >= 50 && m + f < 50 && m + f >= 30){
			printf("C");
		}
		else if(m + f >= 30 && m + f < 50){
			printf("D");
		}
		else if(m + f < 30 || m == -1 || f == -1){
			printf("F");
		}
		printf("\n");
	}
	
	return (0);
}

Compiler output:
main.c: In function 'main':
main.c:21:93: error: expected ')' before '{' token
   21 |                 else if((m + f >= 50 && m + f < 65)|| (r >= 50 && m + f < 50 && m + f >= 30){
      |                        ~                                                                    ^
      |                                                                                             )
main.c:31:9: error: expected expression before '}' token
   31 |         }
      |         ^
Language: C

#include<stdio.h>

int main(){
 int m,f,r;
 while(1){
  scanf("%d %d %d", &m, &f,&r);
  if(m==-1 && f==-1){printf("F\n");}
  else if(m+n>=80){printf("A\n");}
  else if(65<=n+m && n+m<80){printf("B\n");}
  else if(50<=n+m && n+m<65 || r>=50){printf("C\n");}
  else if(30<=n+m && n+m<50 &&r<50){printf("D\n");}
  else if(n+m<30 && r<50){printf("F\n");}
  else if(m==-1 && f==-1 && r==-1){break;}
  else{break;}
 }
 return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:13: error: 'n' undeclared (first use in this function)
    8 |   else if(m+n>=80){printf("A\n");}
      |             ^
main.c:8:13: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include<stdio.h>

int main(){
 int m,f,r;
 while(1){
  scanf("%d %d %d", &m, &f,&r);
  if(m==-1 && f==-1){printf("F\n");}
  else if(m+n>=80){printf("A\n");}
  else if(65<=f+m && f+m<80){printf("B\n");}
  else if(50<=f+m && f+m<65 || r>=50){printf("C\n");}
  else if(30<=f+m && f+m<50 &&r<50){printf("D\n");}
  else if(f+m<30 && r<50){printf("F\n");}
  else if(m==-1 && f==-1 && r==-1){break;}
  else{break;}
 }
 return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:13: error: 'n' undeclared (first use in this function)
    8 |   else if(m+n>=80){printf("A\n");}
      |             ^
main.c:8:13: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>

int main(){
    int m, f, r;
    while(1){
        scanf("%d%d%d", &m, &f, &r);
        
        if(m == -1 && f == -1 && r == -1){break;}
        if(m == -1 || f == -1){printf("C\n");
        }else if(m + f >= 80){printf("A\n");
        }else if(m + f >= 65){printf("B\n");
        }else if(m + f >= 50){printf("C\n");
        }else if(m + f >= 30){
            else if(r >= 50){
                printf("C\n");
            }else(printf("D\n";)
            }
        }else{printf("F\n");
        }
    }
     return 0;
}

Compiler output:
main.c: In function 'main':
main.c:14:13: error: expected '}' before 'else'
   14 |             else if(r >= 50){
      |             ^~~~
main.c:16:31: error: expected ')' before ';' token
   16 |             }else(printf("D\n";)
      |                         ~     ^
      |                               )
main.c:16:33: error: expected ')' before '}' token
   16 |             }else(printf("D\n";)
      |                  ~              ^
      |                                 )
   17 |             }
      |             ~                    
main.c:16:33: error: expected ';' before '}' token
   16 |             }else(printf("D\n";)
      |                                 ^
      |                                 ;
   17 |             }
      |             ~                    
main.c: At top level:
main.c:18:10: error: expected identifier or '(' before 'else'
   18 |         }else{printf("F\n");
      |          ^~~~
main.c:20:5: error: expected identifier or '(' before '}' token
   20 |     }
      |     ^
main.c:21:6: error: expected identifier or '(' before 'return'
   21 |      return 0;
      |      ^~~~~~
main.c:22:1: error: expected identifier or '(' before '}' token
   22 | }
      | ^
Language: C

#include <stdio.h>

int main(){
    int m, f, r;
    while(1){
        scanf("%d%d%d", &m, &f, &r);
        
        if(m == -1 && f == -1 && r == -1){break;}
        if(m == -1 || f == -1){printf("C\n");
        }else if(m + f >= 80){printf("A\n");
        }else if(m + f >= 65){printf("B\n");
        }else if(m + f >= 50){printf("C\n");
        }else if(m + f >= 30){
            if(r >= 50){
                printf("C\n");
            }else(printf("D\n";)
            }
        }else{printf("F\n");
        }
    }
     return 0;
}

Compiler output:
main.c: In function 'main':
main.c:16:31: error: expected ')' before ';' token
   16 |             }else(printf("D\n";)
      |                         ~     ^
      |                               )
main.c:16:33: error: expected ')' before '}' token
   16 |             }else(printf("D\n";)
      |                  ~              ^
      |                                 )
   17 |             }
      |             ~                    
main.c:16:33: error: expected ';' before '}' token
   16 |             }else(printf("D\n";)
      |                                 ^
      |                                 ;
   17 |             }
      |             ~                    
main.c:18:10: error: 'else' without a previous 'if'
   18 |         }else{printf("F\n");
      |          ^~~~
main.c: At top level:
main.c:21:6: error: expected identifier or '(' before 'return'
   21 |      return 0;
      |      ^~~~~~
main.c:22:1: error: expected identifier or '(' before '}' token
   22 | }
      | ^
Language: C

#include <stdio.h>

int main(void)
{
    int m, f, r;
    int sum;
    while (1){
        scanf_s("%d %d %d", &m, &f, &r);
        if (m == -1 && f == -1 && r == -1){
            break;
        }
        
        sum = m + f;
        if ((m == -1 || f == -1) || sum < 30) puts("F");
        if ((30 <= sum && sum < 50) && (m != -1 && f != -1)) { puts("D"); } else if (50 <= f)puts("C");
        if (50 <= sum && sum < 65) puts("C");
        if (65 <= sum && sum < 80) puts("B");
        if (80 <= sum) puts("A");
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:9: error: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    8 |         scanf_s("%d %d %d", &m, &f, &r);
      |         ^~~~~~~
      |         scanf
Language: C

#include<stdio.h>
int main(){

  int m,f,r,i,sum;

  while(1){
    scanf("%d%d%d",&m,&f,&r);

    if(m == -1 && f == -1 && r == -1)break;


    sum=m+f;
    if(80 <= sum){
      printf("A\n");
    }else if(65 <= sum && sum < 80){
      printf("B\n");
    }else if(50 <= sum && sum < 65){
      printf("C\n"); 
    }else if(30 <= sum && sum < 50){
      if(f>=50){
	printf("C\n");
      }else{
	printf("D\n");
      } 
    }else if(sum < 30){
      printf("F\n");
    }
  }
  return 0;

Compiler output:
main.c: In function 'main':
main.c:29:3: error: expected declaration or statement at end of input
   29 |   return 0;
      |   ^~~~~~
Language: C

#include<stdio.h>
int main(){
int a,b,c,m,f,r;
while(1){
scanf("%d %d %d",&m,&f,&r);
if(m==-1&&f==-1&&r==-1)
break;
a=m+f;
if(a>=80)
printf("A\n");
if(a>=65&&a<80)
printf("B\n");
if(m!=-1&&f!=-1&&a>=50&&a<65)
printf("C\n");
if(m!=-1&&f!=-1&&a>=30&&a<50)
printf("D\n");
if(m!=-1&&f!=-1&&a>=30&&a<50&&r>=50)
printf("C\n");
if(m!=-1&&f!=-1&&a>=50&&a<65)
printf("C\n");
if(m!=-1&&f!=-1&&a30)
printf("F\n");
if(m==-1||f==-1)
printf("F\n");
}
}

Compiler output:
main.c: In function 'main':
main.c:21:18: error: 'a30' undeclared (first use in this function)
   21 | if(m!=-1&&f!=-1&&a30)
      |                  ^~~
main.c:21:18: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include<stdio.h>
int main(){
  int m,f,r,sum;
  while(1){
  scanf("%d%d%d",&m,&f,&r);
  if(m==-1 && f==-1 && r==-1) break;
  sum=m+f;
  
  if(sum>=80){
    printf("A\n");
}

  else if(sum>=65){
    printf("B\n");
  }

  else if(sum>=50){
    printf("C\n");
  }

  else if(sum>=30){
    if(r>=50) printf("C\n");
    else printf("D\n");
  }

  else  printf("F\n");
  if(m==-1 && f==-1) printf("F\n);

  }

  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:27:29: warning: missing terminating " character
   27 |   if(m==-1 && f==-1) printf("F\n);
      |                             ^
main.c:27:29: error: missing terminating " character
   27 |   if(m==-1 && f==-1) printf("F\n);
      |                             ^~~~~~
main.c:29:3: error: expected expression before '}' token
   29 |   }
      |   ^
main.c:27:29: error: expected ';' before '}' token
   27 |   if(m==-1 && f==-1) printf("F\n);
      |                             ^
      |                             ;
   28 | 
   29 |   }
      |   ~
Language: C

#include<stdio.h>
main(void){
	int m=0,f=0,r=0;
	while(EOF !=scanf("%d %d %d",&m,&f,&r)){
		
		if(m==-1 && f==-1 && r==-1){
		break;
		}
		
		if(m==-1 || f==-1)			printf("F\n");
		
		else if(m+f>=80)			printf("A\n");
		
		else if(65<=m+f && m+f<80)	printf("B\n");
		
		else if(50<=m+f && m+f<65)	printf("C\n");
		
		else if(m+f>=30 && m+f<50){
			if(r>=50)				printf("C\n");
			else 					printf("D\n");
		}
		
		else 						printf("E\n");
	}
	return 0
}

Compiler output:
main.c:2:1: error: return type defaults to 'int' [-Wimplicit-int]
    2 | main(void){
      | ^~~~
main.c: In function 'main':
main.c:25:17: error: expected ';' before '}' token
   25 |         return 0
      |                 ^
      |                 ;
   26 | }
      | ~
Language: C

#include<stdio.h>
main(void)
{
	int m=0,f=0,r=0;
	while(EOF !=scanf("%d %d %d",&m,&f,&r)){
		
		if(m==-1 && f==-1 && r==-1){
		break;
		}
		
		if(m==-1 || f==-1)			printf("F\n");
		
		else if(m+f>=80)			printf("A\n");
		
		else if(65<=m+f && m+f<80)	printf("B\n");
		
		else if(50<=m+f && m+f<65)	printf("C\n");
		
		else if(m+f>=30 && m+f<50){
			if(r>=50)				printf("C\n");
			else 					printf("D\n");
		}
		
		else 						printf("E\n");
	}
	return 0
}

Compiler output:
main.c:2:1: error: return type defaults to 'int' [-Wimplicit-int]
    2 | main(void)
      | ^~~~
main.c: In function 'main':
main.c:26:17: error: expected ';' before '}' token
   26 |         return 0
      |                 ^
      |                 ;
   27 | }
      | ~
Language: C

#include<stdio.h>
int main(void)
{
	int m=0,f=0,r=0;
	while(EOF !=scanf("%d %d %d",&m,&f,&r)){
		
		if(m==-1 && f==-1 && r==-1){
		break;
		}
		
		if(m==-1 || f==-1)			printf("F\n");
		
		else if(m+f>=80)			printf("A\n");
		
		else if(65<=m+f && m+f<80)	printf("B\n");
		
		else if(50<=m+f && m+f<65)	printf("C\n");
		
		else if(m+f>=30 && m+f<50){
			if(r>=50)				printf("C\n");
			else 					printf("D\n");
		}
		
		else 						printf("E\n");
	}
	return 0
}

Compiler output:
main.c: In function 'main':
main.c:26:17: error: expected ';' before '}' token
   26 |         return 0
      |                 ^
      |                 ;
   27 | }
      | ~
Language: C

#include <stdio.h>

/* ????¨?????????? */
typedef struct tagsExaminationScore {
	int m_score;	/* ??????????¨? */
	int f_score;	/* ??????????¨? */
	int r_score;	/* ???????¨? */
} S_EXAMINATION_SCORE;

int main(void)
{
	S_EXAMINATION_SCORE studentScore;
	char studentGrage;

	while(true) {
		/* ????¨???????????????\??? */
		scanf("%d %d %d", &studentScore.m_score, 
						  &studentScore.f_score,
						  &studentScore.r_score);
		
		/* ??\???????????????-1?????¨??????????????? */
		if(studentScore.m_score == -1 &&
		   studentScore.f_score == -1 &&
		   studentScore.r_score == -1){
			   break;
		   }

		if(studentScore.m_score == -1 || studentScore.f_score == -1){
			/* ??????????¨??????????????¨?????????????????¬???? */
			studentGrage = 'F';
		}else if(80 <= (studentScore.m_score + studentScore.f_score )){
			/* ??????????¨???¨??????????¨????????¨??????°???80??\??? */
			studentGrage = 'A';
		}else if(65 <= (studentScore.m_score + studentScore.f_score ) &&
			/* ??????????¨???¨??????????¨????????¨??????°??? 65 ??\??? 80 ?????? */
				 (studentScore.m_score + studentScore.f_score ) < 80){
			studentGrage = 'B';
			
		}else if(50 <= (studentScore.m_score + studentScore.f_score ) &&
			/* ??????????¨???¨??????????¨????????¨??????°??? 50 ??\??? 65 ?????? */
				 (studentScore.m_score + studentScore.f_score ) < 65){
			studentGrage = 'C';
			
		}else if(30 <= (studentScore.m_score + studentScore.f_score ) &&
				 (studentScore.m_score + studentScore.f_score ) < 50){
			/* ??????????¨???¨??????????¨????????¨??????°??? 30 ??\??? 50 ?????? */
			/* ???????????????????¨?????????°???50 ??\???????????°?????????C */
			if(50 <= studentScore.r_score){
				studentGrage = 'C';
			}else{
				studentGrage = 'D';
			}
		}else if((studentScore.m_score + studentScore.f_score ) < 30){
			/* ??????????¨???¨??????????¨????????¨??????°??? 30 ?????? */
			studentGrage = 'F';
		}else{
			/* do nothing */
		}

		/* ????????¨??? */
		printf("%c\n", studentGrage);
	}

	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:15:15: error: 'true' undeclared (first use in this function)
   15 |         while(true) {
      |               ^~~~
main.c:2:1: note: 'true' is defined in header '<stdbool.h>'; this is probably fixable by adding '#include <stdbool.h>'
    1 | #include <stdio.h>
  +++ |+#include <stdbool.h>
    2 | 
main.c:15:15: note: each undeclared identifier is reported only once for each function it appears in
   15 |         while(true) {
      |               ^~~~
Language: C

#include<iostream>
using namespace std;
int t,k,s;
in out(){
while(1){
cin>>t>>k>>s;
if(t==-1&&k==-1&&s==-1)
break;
if(t==-1||k==-1)
cout<<"F"<<endl;
else if(t+k>=80)
cout<<"A"<<endl;
else if(t+k>=65)
cout<<"B"<<endl;
else if(t+k>=50)
cout<<"C"<<endl;
else if(t+k>=30){
if(s>=50)
cout<<"C"<<endl;
else
cout<<"D"<<endl;
}
else
cout<<"F"<<endl;
}
}
int main(){
out();
retur n0;
}

Compiler output:
main.c:1:9: fatal error: iostream: No such file or directory
    1 | #include<iostream>
      |         ^~~~~~~~~~
compilation terminated.
Language: C

#include<stdio.h>
int main(void){
int m,f,r;
int kekka;
while(1){
scanf("%d %d %d",&m,&f,&r);
kekka=m+f;
if(m==-1&&m==-1&&r==-1){break;}
else{
if((m==-1||f==-1)||(kekka<30)){
printf("F\n");
}else if(kekka<50){
if(r<50){printf("D\n");}
else{printf("C\n");
}else if(kekka<65){
printf("C\n");
}else if(kekka<80){
printf("B\n");
}else{
printf("A\n");
}
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:15:2: error: expected '}' before 'else'
   15 | }else if(kekka<65){
      |  ^~~~
main.c:24:1: error: expected declaration or statement at end of input
   24 | }
      | ^
Language: C

#include<stdio.h>
int main(void){
int m,f,r;
int kekka;
while(1){
scanf("%d %d %d",&m,&f,&r);
kekka=m+f;
if(m==-1&&m==-1&&r==-1){break;}
else{
if((m==-1||f==-1)||(kekka<30)){
printf("F\n");
}else if(kekka<50){
if(r<50){printf("D\n");}
else{printf("C\n");
}else if(kekka<65){
printf("C\n");
}else if(kekka<80){
printf("B\n");
}else{
printf("A\n");
}
}
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:15:2: error: expected '}' before 'else'
   15 | }else if(kekka<65){
      |  ^~~~
Language: C

#include<stdio.h>

int main(){
	int m,f,r,sum;

	while(1){
		scanf("%d %d %d",&m,&f,&r);
		sum = m + f;
		if(sum == -2 && r == -1) break;
		if(sum >= 80) printf("A\n");
		else if(sum >= 65 && sum < 80) printf("B\n");
		else if(sum >= 50 && sum < 65) printf("C\n");
		else if(sum >= 30 && sum < 50 && r >= 50) printf("D\n");
		else if(sum < 30) printf("F\n");
	}
	return 0;

Compiler output:
main.c: In function 'main':
main.c:16:9: error: expected declaration or statement at end of input
   16 |         return 0;
      |         ^~~~~~
Language: C

#include <stdio.h>

int main(void) {

    int m;
    int f;
    int r;
    int total;
    char result;

    while(1) {
        scanf("%d %d %d", &m, &f, &r);

        if(m == -1 && f == -1 && r == -1) {
            break;
        }

        total = m + f;

        if((m == -1 || f == -1) ||
           (total < 30) {
             result = 'F';
        }
        else if(total >= 80) {
             result = 'A';
        }
        else if(total >= 65) {
             result = 'B';
        }
        else if(total >= 50 ||
                total >= 30 && r >= 50) {
             result = 'C';
        }
        else {
             result = 'D';
        }
        
        printf("%c\n", result);
    }
}

Compiler output:
main.c: In function 'main':
main.c:21:24: error: expected ')' before '{' token
   21 |            (total < 30) {
      |                        ^~
      |                        )
main.c:20:11: note: to match this '('
   20 |         if((m == -1 || f == -1) ||
      |           ^
main.c:39:5: error: expected expression before '}' token
   39 |     }
      |     ^
Language: C

#include <stdio.h>

int main(void){
  int m,f,r;
  int judge;

  scanf("%d%d%d",&m,&f,&r);
  while(m!=-1 || f!=-1 || r!=-1){
    judge=0;
    
    if(m==-1 || f==-1){
      printf("F\n");
    } else {
      judge=m+f;
      if(judge>=80)  printf("A\n");
      else if(65<=judge && judge<80)  printf("B\n");
      else if(50<=judge && judge<65)  printf("C\n");
      else if(30<=judge && judge<50){
        if(r>=50)  printf("C\n");
        else printf("D\n");
      }  else printf("F\n");

    scanf("%d%d%d",&m,&f,&r);
  }

  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:27:1: error: expected declaration or statement at end of input
   27 | }
      | ^
Language: C

#include <stdio.h>

int main()
{
    int tensu1[1000], tensu2[1000], tensu3[1000];
    int tensu_c[1000];
    int i = 0, j;
    
    while(1){
        scanf("%d %d %d", &tensu1[i], &tensu2[i], &tensu3[i]);
        tensu_c[i] = tensu1[i] + tensu2[i];
        if (tensu1[i] == -1 && tensu2[i] == -1){
            if (tensu3[i] == -1) break;
        }
        i++;
    }
    
    for (j = 0; j < i; j++){
        if (tensu1[j] == -1 || tensu2[j] == -1)
            printf("F\n");
        else if (tensu_c[j] >= 80){
            printf("A\n");
            break;
        }
        else if (65 <= tensu_c[j] && tensu_c[j] < 80){
            printf("B\n");
            break;
        }
        else if (50 <= tensu_c[j] && tensu_c[j] < 65){
            printf("C\n");
            break;
        }
        else if (30 <= tensu_c[j] && tensu_c[j] < 50){
            printf("D\n");
            break;
        }
        else if (tesu1[j] != -1 && tensu2[j] != -1){
            if (tensu3[j] >= 50) 
                printf("C\n");
            break;
        }
        else if (tensu_c[j] < 30){
            printf("F\n");
            break;
        }
    }
    
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:37:18: error: 'tesu1' undeclared (first use in this function); did you mean 'tensu1'?
   37 |         else if (tesu1[j] != -1 && tensu2[j] != -1){
      |                  ^~~~~
      |                  tensu1
main.c:37:18: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>

int main(){

  int m,f,r,sum;
  for(;;){
    scanf("%d%d%d",&m,&f,&r);
  
    sum=m+f;
 
    if(m==-1&&f==-1&&r==-1){break;}
    else if(sum<=100&&sum>=80) {printf("A\n");}
    else if(sum>=65&&sum<80) {printf("B\n");}
    else if(sum>=50&&sum<65) {printf("C\n");}
    else if(sum>=30&&sum<50) { 
                             printf("D\n");
         if(r>=50)           {printf("C\n");}
    else if(sum<30&&r==-1)   {printf("F\n");}
    else if(m==-1||f==-1)    {printf("F\n");}
 }

  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:23:1: error: expected declaration or statement at end of input
   23 | }
      | ^
Language: C

#include<iostream>
using namespace std;

int main() {
	int m, f, r;
	
	while(1){
		cin >> m >> f >> r;

		if (m == -1 && f == -1 && r == -1)
			break;
		else if (m == -1 && f == -1)
			cout << 'F' << endl;
		else if (m + f >= 80)
			cout << 'A' << endl;
		else if (m + f >= 65 && m + f < 80)
			cout << 'B' << endl;
		else if (m + f < 65 && m + f >= 50)
			cout << 'C' << endl;
		else if (m + f >= 30 && m + f < 50)
			if (r >= 50)
				cout << 'C' << endl;
			else cout << 'D' << endl;
		}
		else cout << 'F' << endl;
	}

	return 0;
}

Compiler output:
main.c:1:9: fatal error: iostream: No such file or directory
    1 | #include<iostream>
      |         ^~~~~~~~~~
compilation terminated.
Language: C

#include<stdio.h>
int main(void)
{
	int a,b,c,d;
	c=0;
	for(;;){
		for(b=1;b<=3;b++){
			scanf("%d",&a);
			if(a==-1){
				a=-100;
			}
			c+=a;
		}
		if(c<-150){
			break;
		}
		if(c<30){
			printf("F\n");
		}else{
			if(c<50){
				printf("D\n");
			}
		}else{
			if(c<65){
				printf("C\n");
			}
		}else{
			if(c<80){
				printf("B\n");
			}
		}else{
			printf("A\n");
		}
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:23:18: error: 'else' without a previous 'if'
   23 |                 }else{
      |                  ^~~~
main.c:27:18: error: 'else' without a previous 'if'
   27 |                 }else{
      |                  ^~~~
main.c:31:18: error: 'else' without a previous 'if'
   31 |                 }else{
      |                  ^~~~
Language: C

#include <stdio.h>

int main()
{

    int m, f, r, sum;

    while(1){
        scanf("%d %d %d", &m, &f, &r);

        if(m+f+r == -3){break;}

        sum = m + f;    
    
        if(m == -1 || f == -1 || sum < 30){
            printf("F\n");
        }
        if(sum >= 80){
            printf("A\n");
        }
        if(sum >= 65 && sum < 80){
            printf("B\n");
        if(sum >= 50 && sum < 65){
            printf("C\n");
        }
        if(sum >= 30 && sum < 50){
            if(r >= 50){
                printf("C\n");
            }
            else{
                printf("D\n");
            }
        }
    }
    return 0;
}
        

         

Compiler output:
main.c: In function 'main':
main.c:36:1: error: expected declaration or statement at end of input
   36 | }
      | ^
Language: C

#include <stdio.h>
char Grading(m,f,r){
	int t;
	char grade;
	t=m+f
	
	if(m==-1||f==-1){
			grade='F';
		}
	else if(t>=80){
		grade='A';
	}
	else if(t>=65&&t<80){
		grade='B';
	}
	else if(t>=50&&t<65){
		grade='C';
	}
	else if(t>=30&&t<50){
		if(r>=50){
			grade='C';
		}
		else{
			grade='D';
		}
	}
	else{
		grade='F';
	}

	return grade;
}


int main(void){

	int m,f,r;
	char grade;
	
	while(1){
		scanf("%d %d %d",&m,&f,&r);
		if(m==-1&&f==-1&&r==-1){
			break;
		}
		grade=Grading(m,f,r);
		printf("%d\n",grade);
	}

	return 0;
}

Compiler output:
main.c: In function 'Grading':
main.c:2:6: error: type of 'm' defaults to 'int' [-Wimplicit-int]
    2 | char Grading(m,f,r){
      |      ^~~~~~~
main.c:2:6: error: type of 'f' defaults to 'int' [-Wimplicit-int]
main.c:2:6: error: type of 'r' defaults to 'int' [-Wimplicit-int]
main.c:5:14: error: expected ';' before 'if'
    5 |         t=m+f
      |              ^
      |              ;
    6 | 
    7 |         if(m==-1||f==-1){
      |         ~~
Language: C

#include<stdio.h>
int main(){
  int m,f,r;
  while(1){
    scanf("%d %d %d",&m,&f,&r);
    if(m==-1 && f==-1 && r==-1)break;
  }
    else if(m+f<30 ||m==-1 ||f==-1)printf("F\n");
    else if((m+f>50 && m+f<65) || r>=50){
      printf("C\n");
      continue;
    }
    else  if(m+f>=30 && m+f<50)printf("D\n");
    else if(m+f>65 && m+f<80)printf("B\n");
    else if(m+f>=80)printf("A\n");
  }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:5: error: 'else' without a previous 'if'
    8 |     else if(m+f<30 ||m==-1 ||f==-1)printf("F\n");
      |     ^~~~
main.c:11:7: error: continue statement not within a loop
   11 |       continue;
      |       ^~~~~~~~
main.c: At top level:
main.c:17:5: error: expected identifier or '(' before 'return'
   17 |     return 0;
      |     ^~~~~~
main.c:18:1: error: expected identifier or '(' before '}' token
   18 | }
      | ^
Language: C

#include<stdio.h>

#define EXAM 3

int main(void) {
char record[];
int m,f,r;
int count=0;
int i;

while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
record[count] = record_add(m, f, m+f, r);
count++;
}
for (i = 0; i < count-1; i++) {
printf("%c\n", record[i]);
}

return (0);
}

char record_add(int m, int f, int mf, int r) {
if(m == -1 || f == -1) return 'F';
if(mf >= 80) return 'A';
else if (mf >= 65) return 'B';
else if (mf >= 50) return 'C';
else if (mf >= 30 && r >= 50) return 'C';
else if (mf >= 30) return 'D';
else return 'F';
}

Compiler output:
main.c: In function 'main':
main.c:6:6: error: array size missing in 'record'
    6 | char record[];
      |      ^~~~~~
main.c:11:13: error: expected expression before '%' token
   11 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |             ^
main.c:11:21: warning: missing terminating " character
   11 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |                     ^
main.c:11:21: error: missing terminating " character
   11 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:13:9: error: expected ')' before '}' token
   13 | count++;
      |         ^
      |         )
   14 | }
      | ~        
main.c:11:6: note: to match this '('
   11 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |      ^
main.c:14:1: error: expected expression before '}' token
   14 | }
      | ^
main.c: At top level:
main.c:15:1: error: expected identifier or '(' before 'for'
   15 | for (i = 0; i < count-1; i++) {
      | ^~~
main.c:15:15: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   15 | for (i = 0; i < count-1; i++) {
      |               ^
main.c:15:27: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   15 | for (i = 0; i < count-1; i++) {
      |                           ^~
main.c:19:1: error: expected identifier or '(' before 'return'
   19 | return (0);
      | ^~~~~~
main.c:20:1: error: expected identifier or '(' before '}' token
   20 | }
      | ^
Language: C

#include<stdio.h>

int main(void) {
char record[];
int m,f,r;
int count=0;
int i;

while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
record[count] = record_add(m, f, m+f, r);
count++;
}
for (i = 0; i < count-1; i++) {
printf("%c\n", record[i]);
}

return (0);
}

char record_add(int m, int f, int mf, int r) {
if(m == -1 || f == -1) return 'F';
if(mf >= 80) return 'A';
else if (mf >= 65) return 'B';
else if (mf >= 50) return 'C';
else if (mf >= 30 && r >= 50) return 'C';
else if (mf >= 30) return 'D';
else return 'F';
}

Compiler output:
main.c: In function 'main':
main.c:4:6: error: array size missing in 'record'
    4 | char record[];
      |      ^~~~~~
main.c:9:13: error: expected expression before '%' token
    9 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |             ^
main.c:9:21: warning: missing terminating " character
    9 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |                     ^
main.c:9:21: error: missing terminating " character
    9 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:11:9: error: expected ')' before '}' token
   11 | count++;
      |         ^
      |         )
   12 | }
      | ~        
main.c:9:6: note: to match this '('
    9 | while(scanf(%d %d %d",m , f, r), m != -1 && f != -1 && r != -1) {
      |      ^
main.c:12:1: error: expected expression before '}' token
   12 | }
      | ^
main.c: At top level:
main.c:13:1: error: expected identifier or '(' before 'for'
   13 | for (i = 0; i < count-1; i++) {
      | ^~~
main.c:13:15: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   13 | for (i = 0; i < count-1; i++) {
      |               ^
main.c:13:27: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   13 | for (i = 0; i < count-1; i++) {
      |                           ^~
main.c:17:1: error: expected identifier or '(' before 'return'
   17 | return (0);
      | ^~~~~~
main.c:18:1: error: expected identifier or '(' before '}' token
   18 | }
      | ^
Language: C

#include<stdio.h>

int main(void) {
char record[];
int m,f,r;
int count=0;
int i;

while(scanf(%d %d %d",&m , &f, &r), m != -1 && f != -1 && r != -1) {
record[count] = record_add(m, f, m+f, r);
count++;
}
for (i = 0; i < count-1; i++) {
printf("%c\n", record[i]);
}

return (0);
}

char record_add(int m, int f, int mf, int r) {
if(m == -1 || f == -1) return 'F';
if(mf >= 80) return 'A';
else if (mf >= 65) return 'B';
else if (mf >= 50) return 'C';
else if (mf >= 30 && r >= 50) return 'C';
else if (mf >= 30) return 'D';
else return 'F';
}

Compiler output:
main.c: In function 'main':
main.c:4:6: error: array size missing in 'record'
    4 | char record[];
      |      ^~~~~~
main.c:9:13: error: expected expression before '%' token
    9 | while(scanf(%d %d %d",&m , &f, &r), m != -1 && f != -1 && r != -1) {
      |             ^
main.c:9:21: warning: missing terminating " character
    9 | while(scanf(%d %d %d",&m , &f, &r), m != -1 && f != -1 && r != -1) {
      |                     ^
main.c:9:21: error: missing terminating " character
    9 | while(scanf(%d %d %d",&m , &f, &r), m != -1 && f != -1 && r != -1) {
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:11:9: error: expected ')' before '}' token
   11 | count++;
      |         ^
      |         )
   12 | }
      | ~        
main.c:9:6: note: to match this '('
    9 | while(scanf(%d %d %d",&m , &f, &r), m != -1 && f != -1 && r != -1) {
      |      ^
main.c:12:1: error: expected expression before '}' token
   12 | }
      | ^
main.c: At top level:
main.c:13:1: error: expected identifier or '(' before 'for'
   13 | for (i = 0; i < count-1; i++) {
      | ^~~
main.c:13:15: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   13 | for (i = 0; i < count-1; i++) {
      |               ^
main.c:13:27: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   13 | for (i = 0; i < count-1; i++) {
      |                           ^~
main.c:17:1: error: expected identifier or '(' before 'return'
   17 | return (0);
      | ^~~~~~
main.c:18:1: error: expected identifier or '(' before '}' token
   18 | }
      | ^
Language: C

#include <stdio.h>
int min(void)
{
	int m,f,r,i;


	for(i=0;i>0i++)
 {
        scnaf("%d %d %d"&m,&f,&r);

	if(m==-1&&f==-1&&r==-1)
 	{
		i =	i*-1;
	}
else{

	if(m==-1||f==-1)
	{
		printf("F");
	}
	else
	{

		if(m+f>=80)
		{
			printf("A");
		}	
	
		if(m+f>=65&&m+f<80)
		{
			printf("B");
		}

		if(m+f>=50||m+f<65)
		{
			if(r>=50)
			{
				printf("C");
			}
			else
			{
				printf("D");
			}	
			

		if(m+f>=30||m+f)
		{
			printf("F");
		}

	}
     }
  }
	return0;



}

Compiler output:
main.c: In function 'min':
main.c:7:21: error: lvalue required as increment operand
    7 |         for(i=0;i>0i++)
      |                     ^~
main.c:7:23: error: expected ';' before ')' token
    7 |         for(i=0;i>0i++)
      |                       ^
      |                       ;
main.c:9:9: error: implicit declaration of function 'scnaf'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |         ^~~~~
      |         scanf
main.c:9:25: error: invalid operands to binary & (have 'char *' and 'int')
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |               ~~~~~~~~~~^
      |               |
      |               char *
main.c:54:9: error: 'return0' undeclared (first use in this function)
   54 |         return0;
      |         ^~~~~~~
main.c:54:9: note: each undeclared identifier is reported only once for each function it appears in
main.c:58:1: error: expected declaration or statement at end of input
   58 | }
      | ^
Language: C

#include <stdio.h>
int main(void)
{
	int m,f,r,i;


	for(i=0;i>0i++)
 {
        scnaf("%d %d %d"&m,&f,&r);

	if(m==-1&&f==-1&&r==-1)
 	{
		i =	i*-1;
	}
else{

	if(m==-1||f==-1)
	{
		printf("F");
	}
	else
	{

		if(m+f>=80)
		{
			printf("A");
		}	
	
		if(m+f>=65&&m+f<80)
		{
			printf("B");
		}

		if(m+f>=50||m+f<65)
		{
			if(r>=50)
			{
				printf("C");
			}
			else
			{
				printf("D");
			}	
			

		if(m+f>=30||m+f)
		{
			printf("F");
		}

	}
     }
  }
	return 0;



}

Compiler output:
main.c: In function 'main':
main.c:7:21: error: lvalue required as increment operand
    7 |         for(i=0;i>0i++)
      |                     ^~
main.c:7:23: error: expected ';' before ')' token
    7 |         for(i=0;i>0i++)
      |                       ^
      |                       ;
main.c:9:9: error: implicit declaration of function 'scnaf'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |         ^~~~~
      |         scanf
main.c:9:25: error: invalid operands to binary & (have 'char *' and 'int')
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |               ~~~~~~~~~~^
      |               |
      |               char *
main.c:58:1: error: expected declaration or statement at end of input
   58 | }
      | ^
Language: C

#include <stdio.h>
int main(void)
{
	int m,f,r,i;


	for(i=0;i>0i++)
 {
        scnaf("%d %d %d"&m,&f,&r);

	if(m==-1&&f==-1&&r==-1)
 	{
		i =	i*-1;
	}
	
	else
    {

	if(m==-1||f==-1)
	{
		printf("F\n");
	}
	else
	{

		if(m+f>=80)
		{
			printf("A\n");
		}	
	
		if(m+f>=65&&m+f<80)
		{
			printf("B\n");
		}

		if(m+f>=50||m+f<65)
		{
			if(r>=50)
			{
				printf("C\n");
			}
			else
			{
				printf("D\n");
			}	
			

		if(m+f>=30||m+f)
		{
			printf("F\n");
		}

	}
     }
  }
	return 0;



}

Compiler output:
main.c: In function 'main':
main.c:7:21: error: lvalue required as increment operand
    7 |         for(i=0;i>0i++)
      |                     ^~
main.c:7:23: error: expected ';' before ')' token
    7 |         for(i=0;i>0i++)
      |                       ^
      |                       ;
main.c:9:9: error: implicit declaration of function 'scnaf'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |         ^~~~~
      |         scanf
main.c:9:25: error: invalid operands to binary & (have 'char *' and 'int')
    9 |         scnaf("%d %d %d"&m,&f,&r);
      |               ~~~~~~~~~~^
      |               |
      |               char *
main.c:60:1: error: expected declaration or statement at end of input
   60 | }
      | ^
Language: C

#include <stdio.h> 

int main(void)
{	
	int m, f, r, sum;

	while(1)
	{
		scanf("%d %d %d",&m, &f, &r);

		sum = m + f;

		if((m == -1) && (f == -1) && (r == -1))
		{
			break;
		}
		else if((m == -1) || (f == -1))
		{
			printf("F\n");
		}
		else if(sum >=80)
		{
			printf("A\n");
		}
		else if(sum >= 65)
		{
			printf("B\n");
		}
		else if(sum >= 50)
		{
			printf("C\n");
		}
		else if((sum >= 30) &&(r >=50))
		{
			printf("C\n");
		}
		else if(sum >= 30)
		{
			printf("D\n");
		}
		else
		{
			printf("F\n");
		}
	}

Compiler output:
main.c: In function 'main':
main.c:45:9: error: expected declaration or statement at end of input
   45 |         }
      |         ^
Language: C

#include <stdio.h>

int m,f,r;

main(){
	while(1){
		scanf("%d %d %d",&m,&f,&r);
		if(m != -1 && f != -1 && r != -1){
			if(m == -1 || f == -1 || m+f <30){
				printf("F\n");
			}else if(m+f >=80){
				printf("A\n");
			}else if(m+f >=65){
				printf("B\n");
			}else if(m+f >=50 || r >=50){
				printf("C\n");
			}else of(m+r >=30){
				printf("D\n");
		}else{
			break;
		}
	}
	return 0;
}
		
	

Compiler output:
main.c:5:1: error: return type defaults to 'int' [-Wimplicit-int]
    5 | main(){
      | ^~~~
main.c: In function 'main':
main.c:17:31: error: implicit declaration of function 'of'; did you mean 'feof'? [-Wimplicit-function-declaration]
   17 |                         }else of(m+r >=30){
      |                               ^~
      |                               feof
main.c:17:43: error: expected ';' before '{' token
   17 |                         }else of(m+r >=30){
      |                                           ^
      |                                           ;
main.c:24:1: error: expected declaration or statement at end of input
   24 | }
      | ^
Language: C

#include <stdio.h>

int m,f,r;

main(){
	while(1){
		scanf("%d %d %d",&m,&f,&r);
		if(m != -1 && f != -1 && r != -1){
			if(m == -1 || f == -1 || m+f <30){
				printf("F\n");
			}else if(m+f >=80){
				printf("A\n");
			}else if(m+f >=65){
				printf("B\n");
			}else if(m+f >=50 || r >=50){
				printf("C\n");
			}else of(m+r >=30){
				printf("D\n");
			}
		}else{
			break;
		}
	}
	return 0;
}
		
	

Compiler output:
main.c:5:1: error: return type defaults to 'int' [-Wimplicit-int]
    5 | main(){
      | ^~~~
main.c: In function 'main':
main.c:17:31: error: implicit declaration of function 'of'; did you mean 'feof'? [-Wimplicit-function-declaration]
   17 |                         }else of(m+r >=30){
      |                               ^~
      |                               feof
main.c:17:43: error: expected ';' before '{' token
   17 |                         }else of(m+r >=30){
      |                                           ^
      |                                           ;
Language: C

#include <stdio.h>



int main(void) {

	// 1_7-A Grading
	
	int m,f,r;
	int i;
	char result;

	scanf("%d",&m);
	scanf("%d",&f);
	scanf("%d",&r);

	while( (m!=-1) && (f!=-1) && (r!=-1) ){
		if( (m==-1) || (f==-1) ){
			result = 'F';
		}else if( (m+f) < 30 ){
			result = 'F';
		}else if( (m+f) < 50 ){
			result = 'D';
		}else if( (m+f) < 65 ){
			result = 'C';
		}else if( (m+f) < 80 ){
			result = 'B';
		}else{
			result = 'A';
		}
		printf("%c\n",resutl);
		
		scanf("%d",&m);
		scanf("%d",&f);
		scanf("%d",&r);
	}

	return 0;

}

Compiler output:
main.c: In function 'main':
main.c:31:31: error: 'resutl' undeclared (first use in this function); did you mean 'result'?
   31 |                 printf("%c\n",resutl);
      |                               ^~~~~~
      |                               result
main.c:31:31: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>



int main(void) {

	// 1_7-A Grading
	
	int m,f,r;
	int i;
	char result;

	scanf("%d",&m);
	scanf("%d",&f);
	scanf("%d",&r);

	while( (m!=-1) || (f!=-1) || (r!=-1) ){
		if( (m==-1) || (f==-1) ){
			result = 'F';
		}else if( (m+f) < 30 ){
			result = 'F';
		}else if( (m+f) < 50 ){
			if( 50 <= r ){
				result = 'D';
			}
				result = 'F';
			}
		}else if( (m+f) < 65 ){
			result = 'C';
		}else if( (m+f) < 80 ){
			result = 'B';
		}else{
			result = 'A';
		}
		printf("%c\n",result);
		
		scanf("%d",&m);
		scanf("%d",&f);
		scanf("%d",&r);
	}

	return 0;

}

Compiler output:
main.c: In function 'main':
main.c:28:18: error: 'else' without a previous 'if'
   28 |                 }else if( (m+f) < 65 ){
      |                  ^~~~
main.c: At top level:
main.c:42:9: error: expected identifier or '(' before 'return'
   42 |         return 0;
      |         ^~~~~~
main.c:44:1: error: expected identifier or '(' before '}' token
   44 | }
      | ^
Language: C

#include<stdio.h>
int main()
{
int m[1000],f[1000],r[1000],i,sum;
for(i=0;i<1000;i++){
scanf("%d %d %d",&m[i],&f[i],&r[i]);
if((m[i]==-1)&&(f[i]==-1)&&(r[i]==-1))
break;
}
for(i=0;i<1000;i++){
if((m[i]==-1)&&(f[i]==-1)&&(r[i]==-1))
break;
sum=0;
sum=m[i]+f[i];
if(sum>=80)
printf("A\n");
else if(sum>=65)
printf("B\n");
else if(sum>=50)
printf("C\n");
else if(sum>=30){
if(r[i]>=50)
printf("C\n");
else
printf("D\n");
}else
printf("F\n");
}
return 0;
}
for(i=0;i<1000;i++){
sum=0;
sum=m[i]+f[i];
if(sum>=80)
printf("A\n");
else if(sum>=65)
printf("B\n");
else if(sum>=50)
printf("C\n");
else if(sum>=30){
if(r[i]>=50)
printf("C\n");
else
printf("D\n");
}else
printf("F\n");
}
return 0;
}

Compiler output:
main.c:31:1: error: expected identifier or '(' before 'for'
   31 | for(i=0;i<1000;i++){
      | ^~~
main.c:31:10: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   31 | for(i=0;i<1000;i++){
      |          ^
main.c:31:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   31 | for(i=0;i<1000;i++){
      |                 ^~
main.c:48:1: error: expected identifier or '(' before 'return'
   48 | return 0;
      | ^~~~~~
main.c:49:1: error: expected identifier or '(' before '}' token
   49 | }
      | ^
Language: C

#include<stdio.h>
#include<stdlib.h>


int main(void){
	int m,f,r,pls;
	scanf("%d %d %d"m,f,r);
	pls=m+f;
	if("m==-1 || f==-1 || pls<30"){
		printf("F\n");
	}else if("pls>=80"){
		printf("A\n");
	}else if(pls<80 && pls>=65){
		printf("B\n");
	}else if(pls<65 && pls>=50 || pls<50 && pls>=30 && r>=50){
		printf("C\n");
	}else if(pls<50 && pls>=30 && r<50){
		printf("D\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:7:25: error: expected ')' before 'm'
    7 |         scanf("%d %d %d"m,f,r);
      |              ~          ^
      |                         )
Language: C

#include<stdio.h>

int main(void)
{
	int cen,end,again,ab;
	int i;
	printf("??????????????£?????\????????????????????????\n");
	scanf("%d %d %d",&cen,&end,&again);
	
		ab=cen+end;
		
		if(cen==-1||end==-1){
	printf("F\n");
		}else if(ab>=80)
		printf("A\n");
	}else if(ab>=65&&ab<80){
		printf("B\n");
	}else if(ab>=50&&ab<65||again>=50){
		printf("C\n");
	}else if(ab>=30&&ab<50){
		printf("D\n");
	}else{
	printf("F\n");
	}
		

	return 0;
}

Compiler output:
main.c:16:10: error: expected identifier or '(' before 'else'
   16 |         }else if(ab>=65&&ab<80){
      |          ^~~~
main.c:18:10: error: expected identifier or '(' before 'else'
   18 |         }else if(ab>=50&&ab<65||again>=50){
      |          ^~~~
main.c:20:10: error: expected identifier or '(' before 'else'
   20 |         }else if(ab>=30&&ab<50){
      |          ^~~~
main.c:22:10: error: expected identifier or '(' before 'else'
   22 |         }else{
      |          ^~~~
main.c:27:9: error: expected identifier or '(' before 'return'
   27 |         return 0;
      |         ^~~~~~
main.c:28:1: error: expected identifier or '(' before '}' token
   28 | }
      | ^
Language: C

#include <stdio.h>
int main(void){
	int n=0,m=0,i=0;
	int t[100],k[100],s[100];

	while((t[i-1] != -1) && (k[i-1] != -1)){
		scanf("%d %d %d",&t[i],&k[i],&s[i]);
		i++;
		n++;
	}
	i = 0;
	while(m != n-1){
		if(t[i]==-1 || k[i]==-1)
			printf("F\n");
		if(t[i]+k[i]<=30)
			printf("F\n);
		if((30<=t[i]+k[i] && t[i]+k[i]<50) && s[i]<50)
			printf("D\n");
		if(50<=t[i]+k[i] && t[i]+k[i]<65 || (30<=t[i]+k[i] && t[i]+k[i]<50) && s[i]>=50)
			printf("C\n");
		if(65<=t[i]+k[i] && t[i]+k[i]<80)
			printf("B\n");
		if(80<=t[i]+k[i])
			printf("A\n");
		i++;
		m++;
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:16:32: warning: missing terminating " character
   16 |                         printf("F\n);
      |                                ^
main.c:16:32: error: missing terminating " character
   16 |                         printf("F\n);
      |                                ^~~~~~
main.c:17:17: error: expected expression before 'if'
   17 |                 if((30<=t[i]+k[i] && t[i]+k[i]<50) && s[i]<50)
      |                 ^~
main.c:26:21: error: expected ';' before '}' token
   26 |                 m++;
      |                     ^
      |                     ;
   27 |         }
      |         ~
Language: C

#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include<stdio.h>

int main() {
	int m, f, r;
	char rank[5][2] = {"A", "B", "C", "D", "F"};
	int flug;
	while (1) {
		scanf("%d%d%d", &m, &f, &r);
		if (m + f + r == -3)break;
		if (m + f >= 80) flug = 0;
		else if (m + f >= 65) flug = 1;
		else if (m + f >= 50) flug = 2;
		else if (m + f >= 30) r >= 50 ? flug = 2 : flug = 3;
		else flug = 4;
		printf("%s\n", rank[flug]);
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:15:65: error: lvalue required as left operand of assignment
   15 |                 else if (m + f >= 30) r >= 50 ? flug = 2 : flug = 3;
      |                                                                 ^
Language: C

#include<stdio.h>

int main(void)
{
	int m,f,r;
	char grade;


	wghile(1){
		scanf("%d %d %d",&m,&f,&r);

		if(m==-1 && f ==-1 && r==-1)break;
			
		if(m + f >= 80)grade='A';
		if(m + f >= 65 && m + f < 80)grade='B';
		if(m + f >= 50 && m + f < 65)grade='C';
		if(m + f >= 30 && m + f < 50){
			if(r >=50){
				grade='C'
			}
			else{			
				grade='D';
			}
		}
		if(m + f < 30)grade='F';

		printf("%s\n,grade);
	}
	return 0;
}
	
	

Compiler output:
main.c: In function 'main':
main.c:9:9: error: implicit declaration of function 'wghile' [-Wimplicit-function-declaration]
    9 |         wghile(1){
      |         ^~~~~~
main.c:9:18: error: expected ';' before '{' token
    9 |         wghile(1){
      |                  ^
      |                  ;
main.c:27:24: warning: missing terminating " character
   27 |                 printf("%s\n,grade);
      |                        ^
main.c:27:24: error: missing terminating " character
   27 |                 printf("%s\n,grade);
      |                        ^~~~~~~~~~~~~
main.c:30:1: error: expected declaration or statement at end of input
   30 | }
      | ^
Language: C

#include<stdio.h>

int main(void)
{
	int m,f,r;
	char grade;


	wghile(1){
		scanf("%d %d %d",&m,&f,&r);

		if(m==-1 && f ==-1 && r==-1)break;
			
		if(m + f >= 80)grade='A';
		if(m + f >= 65 && m + f < 80)grade='B';
		if(m + f >= 50 && m + f < 65)grade='C';
		if(m + f >= 30 && m + f < 50){
			if(r >=50){
				grade='C';
			}
			else{			
				grade='D';
			}
		}
		if(m + f < 30)grade='F';

		printf("%s\n,grade);
	}
	return 0;
}
	
	

Compiler output:
main.c: In function 'main':
main.c:9:9: error: implicit declaration of function 'wghile' [-Wimplicit-function-declaration]
    9 |         wghile(1){
      |         ^~~~~~
main.c:9:18: error: expected ';' before '{' token
    9 |         wghile(1){
      |                  ^
      |                  ;
main.c:27:24: warning: missing terminating " character
   27 |                 printf("%s\n,grade);
      |                        ^
main.c:27:24: error: missing terminating " character
   27 |                 printf("%s\n,grade);
      |                        ^~~~~~~~~~~~~
main.c:30:1: error: expected declaration or statement at end of input
   30 | }
      | ^