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

#include<stdio.h>


int main(void){

	double x1,y1 , x2,y2 , x3,y3 , x4,y4;
	int n,i;

	scanf("%d",&n);


	for(i=0;i<n;i++){

		scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1 , &x2,&y2 , &x3,&y3 , &x4,&y4);

		if( fabs( (y2-y1)/(x2-x1) ) == fabs( (y4-y3)/(x4-x3) ) )
			puts("YES");

		else
			puts("NO");

	}

	return 0;

}


double fabs(double a){
	if(a>=0)
		return a;
	else
		return -a;

}#include<stdio.h>


int main(void){

	double x1,y1 , x2,y2 , x3,y3 , x4,y4;
	int n,i;

	scanf("%d",&n);


	for(i=0;i<n;i++){

		scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1 , &x2,&y2 , &x3,&y3 , &x4,&y4);

		if( fabs( (y2-y1)/(x2-x1) ) == fabs( (y4-y3)/(x4-x3) ) )
			puts("YES");

		else
			puts("NO");

	}

	return 0;

}


double fabs(double a){
	if(a>=0)
		return a;
	else
		return -a;

}

Compiler output:
main.c: In function 'main':
main.c:16:21: error: implicit declaration of function 'fabs' [-Wimplicit-function-declaration]
   16 |                 if( fabs( (y2-y1)/(x2-x1) ) == fabs( (y4-y3)/(x4-x3) ) )
      |                     ^~~~
main.c:2:1: note: include '<math.h>' or provide a declaration of 'fabs'
    1 | #include<stdio.h>
  +++ |+#include <math.h>
    2 | 
main.c:16:21: warning: incompatible implicit declaration of built-in function 'fabs' [-Wbuiltin-declaration-mismatch]
   16 |                 if( fabs( (y2-y1)/(x2-x1) ) == fabs( (y4-y3)/(x4-x3) ) )
      |                     ^~~~
main.c:16:21: note: include '<math.h>' or provide a declaration of 'fabs'
main.c: At top level:
main.c:35:2: error: stray '#' in program
   35 | }#include<stdio.h>
      |  ^
main.c:35:10: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   35 | }#include<stdio.h>
      |          ^
main.c:63:8: error: redefinition of 'fabs'
   63 | double fabs(double a){
      |        ^~~~
main.c:29:8: note: previous definition of 'fabs' with type 'double(double)'
   29 | double fabs(double a){
      |        ^~~~
Language: C

#include<stdio.h>

int main(void){
	
	double x1,x2,x3,x4,y1,y2,y3,y4;
	int n,i;
	
	scanf("%d",&n);
	fo(i=0;i<n;i++){
	scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
	
	if((x2-x1)*(y4-y3)-(y2-y1)*(x4-x3)==0){
		printf("YES\n");
	}else{
		printf("NO\n");
	}
	}
	
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:9:9: error: implicit declaration of function 'fo'; did you mean 'feof'? [-Wimplicit-function-declaration]
    9 |         fo(i=0;i<n;i++){
      |         ^~
      |         feof
main.c:9:15: error: expected ')' before ';' token
    9 |         fo(i=0;i<n;i++){
      |           ~   ^
      |               )
main.c:9:24: error: expected ';' before '{' token
    9 |         fo(i=0;i<n;i++){
      |                        ^
      |                        ;
Language: C

//AOJ 0021
#include <stdio.h>
//x???y?????????????????????????????????????????????
int main(){
    double x1,y1,x2,y2,x3,y3,x4,y4;
    double m1,m2;
    int n,i;
    scanf("%d",&n);
    for(i=0;i<n;i++){
    	scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    	m1=(y2-y1)/(x2-x1);
    	m2=(y4-y3)/(x4-x3);
    	if(m1==m2)puts("YES");
    	else puts("NO");
    	}
	}
	return 0;
}

Compiler output:
main.c:17:9: error: expected identifier or '(' before 'return'
   17 |         return 0;
      |         ^~~~~~
main.c:18:1: error: expected identifier or '(' before '}' token
   18 | }
      | ^
Language: C

//AOJ 0021
#include <stdio.h>
int main(){
    double x1,y1,x2,y2,x3,y3,x4,y4;
    double m1,m2,n1,n2;
    int n,i;
    scanf("%d",&n);
    for(i=0;i<n;i++){
    	scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    	m1=(y2-y1);
        n1=(x2-x1);
    	m2=(y4-y3);
        n2=(x4-x3);
if(n1==0){
 if(n2==0){
  if(n1==n2)puts("YES");
  else puts("NO");
 }else puts("NO");
}else if(n2==0){
puts("NO");
else{if(m1/n1==m2/n2)puts("YES");
    	else puts("NO");
    	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:21:1: error: expected '}' before 'else'
   21 | else{if(m1/n1==m2/n2)puts("YES");
      | ^~~~
main.c:25:1: error: expected declaration or statement at end of input
   25 | }
      | ^
Language: C

//AOJ 0021
#include <stdio.h>
int main(){
    double x1,y1,x2,y2,x3,y3,x4,y4;
    double m1,m2,n1,n2;
    int n,i;
    scanf("%d",&n);
    for(i=0;i<n;i++){
    	scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    	m1=(y2-y1);
        n1=(x2-x1);
    	m2=(y4-y3);
        n2=(x4-x3);
if(n1==0){
 if(n2==0){
  if(n1==n2)puts("YES");
  else puts("NO");
 }else puts("NO");
}else if(n2==0){
puts("NO");}
else{if(m1/n1==m2/n2)puts("YES");
    	else puts("NO");
    	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:25:1: error: expected declaration or statement at end of input
   25 | }
      | ^
Language: C

//AOJ 0021
#include <stdio.h>
int main(){
    double x1,y1,x2,y2,x3,y3,x4,y4;
    double m1,m2,n1,n2;
    int n,i;
    scanf("%d",&n);
    for(i=0;i<n;i++){
    	scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    	m1=(y2-y1);
        n1=(x2-x1);
    	m2=(y4-y3);
        n2=(x4-x3);
if(n1==0){
 if(n2==0){
  if(n1==n2)puts("YES");
  else puts("NO");
 }else puts("NO");
}else if(n2==0){
puts("NO");}
else{if(m1/n1==m2/n2)puts("YES");
    	else puts("NO");
    	
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:25:1: error: expected declaration or statement at end of input
   25 | }
      | ^
main.c:25:1: error: expected declaration or statement at end of input
Language: C

#include <stdio.h>

int main(void){
  double x1,y1,x2,y2,x3,y3,x4,y4;
  double dm,dn;
  int i,n;

  scanf("%d",&n);

  for(i=0;i<n;i++){
    dm=dn=0;
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    if(x1==x2&&)
    dm=(y1-y2)/(x1-x2);
    dn=(y3-y4)/(x3-y4);

    if(dm == dn){
      printf("YES\n");
    } else {
      printf("NO\n");
    }
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:13:16: error: expected expression before ')' token
   13 |     if(x1==x2&&)
      |                ^
Language: C

#include <stdio.h>

int main(void){
  double x1,y1,x2,y2,x3,y3,x4,y4;
  double dm,dn;
  int i,n;

  scanf("%d",&n);

  for(i=0;i<n;i++){
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    if(x1 == x2 && x3 == x4){
      printf("YES\n");
      continue;
    }
    if(x1 != x2 && x3 == x4){
      printf("NO\n");
      continue;
    }
    if(x1 == x2 && x3 != x4){
      prtinf("NO\n");
      continue;
    }

    dm=(y1-y2)/(x1-x2);
    dn=(y3-y4)/(x3-y4);

    if(dm == dn){
      printf("YES\n");
    } else {
      printf("NO\n");
    }
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:21:7: error: implicit declaration of function 'prtinf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   21 |       prtinf("NO\n");
      |       ^~~~~~
      |       printf
Language: C

#include<stdio.h>
?? 
int main(void){
?? int n;
?? int i = 0;
?? float x1,y1,x2,y2,x3,y3,x4,y4;
?? double a,b;
?? 
?? scanf("%d",&n);
?? 
?? while(scanf("%f %f %f %f %f %f %f %f",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4) != EOF){
?? 
?? ?? if( i >= n )break;
?? 
?? ?? a = (y2 - y1) / (x2 - x1);
?? ?? b = (y4 - y3) / (x4 - x3);
?? 
?? ?? if( a == b ){
?? ?? ?? printf("YES\n");
?? ?? }else{
?? ?? ?? printf("NO\n");
?? ?? }
?? 
?? ?? i++;
?? 
?? }
?? 
?? return 0;
}

Compiler output:
main.c:2:1: error: expected identifier or '(' before '?' token
    2 | ??
      | ^
Language: C

int main(void)
{
    double x1, y1, x2, y2, x3, y3, x4, y4;
 
    getchar();getchar();
    while( scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4) != EOF )
    {
        if( (y2-y1)/(x2-x1) == (y4-y3)/(x4-x3) ){ puts("YES"); }
        else{ puts("NO"); }
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:5:5: error: implicit declaration of function 'getchar' [-Wimplicit-function-declaration]
    5 |     getchar();getchar();
      |     ^~~~~~~
main.c:1:1: note: 'getchar' is defined in header '<stdio.h>'; this is probably fixable by adding '#include <stdio.h>'
  +++ |+#include <stdio.h>
    1 | int main(void)
main.c:6:12: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    6 |     while( scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4) != EOF )
      |            ^~~~~
main.c:6:12: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:6:12: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
main.c:6:12: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:6:96: error: 'EOF' undeclared (first use in this function)
    6 |     while( scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4) != EOF )
      |                                                                                                ^~~
main.c:6:96: note: 'EOF' is defined in header '<stdio.h>'; this is probably fixable by adding '#include <stdio.h>'
main.c:6:96: note: each undeclared identifier is reported only once for each function it appears in
main.c:8:51: error: implicit declaration of function 'puts' [-Wimplicit-function-declaration]
    8 |         if( (y2-y1)/(x2-x1) == (y4-y3)/(x4-x3) ){ puts("YES"); }
      |                                                   ^~~~
main.c:8:51: note: include '<stdio.h>' or provide a declaration of 'puts'
Language: C

#include <stdio.h>
#include <math.h>

int main(void) {
	int n, i;
	double x1, x2, x3, x4, y1, y2, y3, y4;
	
	for(i=0, i<n, i++){
		scanf("%d %d %d %d %d %d %d %d", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
		
		if(fabs((y1-y2)/(x1-x2))==fabs((y3-y4)/(x3-x4)))
		printf("YES\n");
		
		else printf("NO\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:26: error: expected ';' before ')' token
    8 |         for(i=0, i<n, i++){
      |                          ^
      |                          ;
main.c:8:26: error: expected expression before ')' token
Language: C

#include <stdio.h>

int main(void) {
    double x0, x1;
    double y0, y1;
 
    double x2, x3;
    double y2, y3;
 
    int dataset, i;
 
    scanf("%d", &dataset);
     
    for(i = 0; i < dataset; i++) {
        while(scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x0, &x1, &y0, &y1, &x2, &x3, &y2, &y3) != EOF) {
 
                if(y1 - y0)/(x1 - x0) == (y3 - y2)/(x3 - x2)){
                      printf("YES\n");
                 }
                 else{
                     printf("NO\n");
                 }
        }
    }
}

Compiler output:
main.c: In function 'main':
main.c:17:28: error: expected expression before '/' token
   17 |                 if(y1 - y0)/(x1 - x0) == (y3 - y2)/(x3 - x2)){
      |                            ^
main.c:17:61: error: expected statement before ')' token
   17 |                 if(y1 - y0)/(x1 - x0) == (y3 - y2)/(x3 - x2)){
      |                                                             ^
main.c:20:18: error: 'else' without a previous 'if'
   20 |                  else{
      |                  ^~~~
Language: C

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

  double x1,y1,x2,y2,x3,y3,x4,y4;
  double t_x1,t_y1,t_x2,t_y2;
  double result;
  int dataset;
  int i; 
   
  scanf("%d",&n);
 
  for(i = 0;i < dataset; ++i){
    scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
     
    t_x1 = x1 - x2;
    t_y1 = y1 - y2;
    t_x2 = x3 - x4;
    t_y2 = y3 - y4;
     
    result= t_x1 * t_y2 - t_y1 * t_x2;
     
    if(result <= 1e-10 && result >= -1e-10){
      printf("YES\n");
    }
    else{
      printf("NO\n");
    }
     
  }
}

Compiler output:
main.c: In function 'main':
main.c:11:15: error: 'n' undeclared (first use in this function)
   11 |   scanf("%d",&n);
      |               ^
main.c:11:15: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include<stdio.h>

int main(void) {
    float x0, x1;
    float y0, y1;

    float x2, x3;
    float y2, y3;

    int dataset;
    
    scanf("%d", &dataset);

    int i
    for(int i = 0; i < dataset; i++) {
        while(scanf("%f %f %f %f %f %f %f %f", &x0, &x1, &y0, &y1, &x2, &x3, &y2, &y3) != EOF) {

                (y1 - y0)/(x1 - x0) == (y3 - y2)/(x3 - x2) ? printf("YES\n") : printf("NO\n");
        }
    }
}

Compiler output:
main.c: In function 'main':
main.c:15:5: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'for'
   15 |     for(int i = 0; i < dataset; i++) {
      |     ^~~
Language: C

#include<stdio.h>

int main(void) {
    float x0, x1;
    float y0, y1;

    float x2, x3;
    float y2, y3;

    int dataset;
    
    scanf("%d", &dataset);

    int i
    for(i = 0; i < dataset; i++) {
        while(scanf("%f %f %f %f %f %f %f %f", &x0, &x1, &y0, &y1, &x2, &x3, &y2, &y3) != EOF) {

                (y1 - y0)/(x1 - x0) == (y3 - y2)/(x3 - x2) ? printf("YES\n") : printf("NO\n");
        }
    }
}

Compiler output:
main.c: In function 'main':
main.c:15:5: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'for'
   15 |     for(i = 0; i < dataset; i++) {
      |     ^~~
main.c:15:9: error: 'i' undeclared (first use in this function)
   15 |     for(i = 0; i < dataset; i++) {
      |         ^
main.c:15:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
 
int main(void)
{
    float x[4];
    float y[4];
    float num1, num2;
    int dataset, i;
    scanf("%d", &dataset);
 
    while (dataset > 0){
        dataset--;
        for (i = 0; i < 4; i++){
            scanf("%f %f", &x[i], &y[i]);
        }
         
        slope1 = (y[1] - y[0]) / (x[1] - x[0]);
        slope2 = (y[3] - y[2]) / (x[3] - x[2]);
         
        if (slope1 == slope2){
            printf("YES\n");
        }
        else {
            printf("NO\n");
        }
    }
 
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:17:9: error: 'slope1' undeclared (first use in this function)
   17 |         slope1 = (y[1] - y[0]) / (x[1] - x[0]);
      |         ^~~~~~
main.c:17:9: note: each undeclared identifier is reported only once for each function it appears in
main.c:18:9: error: 'slope2' undeclared (first use in this function)
   18 |         slope2 = (y[3] - y[2]) / (x[3] - x[2]);
      |         ^~~~~~
Language: C

#include <stdio.h>
 
int main(void)
{
    float x[4];
    float y[4];
    float slope1, slope2;
    int dataset, i;
    scanf("%d", &dataset);
 
    while (dataset > 0){
        dataset--;
        for (i = 0; i < 4; i++){
            scanf("%f %f", &x[i], &y[i]);
        }
         
        slope1 = (y[1] - y[0]) / (x[1] - x[0]);
        slope2 = (y[3] - y[2]) / (x[3] - x[2]);
         
        if (slope1 == slope2){
            printf("YES\n");
        }
        else {
            printf("NO\n");
        }

Compiler output:
main.c: In function 'main':
main.c:25:9: error: expected declaration or statement at end of input
   25 |         }
      |         ^
main.c:25:9: error: expected declaration or statement at end of input
Language: C

#include<stdio.h>
#include<string.h>

int main(){
	int i,n;
	double x1,y1,x2,y2,x3,y3,x4,y4;
	scanf_s("%d",&n);
	for(i=0;i<n;i++){
		scanf_s("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
		if(x1-x2==0.0 && x3-x4==0.0){
			printf("YES\n");
		}else if(y1-y2==0.0 && y3-y4==0.0){
			printf("YES\n");
		}else if((y2-y1)/(x2-x1)==(y4-y3)/(x4-x3)){
			printf("YES\n");
		}else printf("NO\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:7:9: error: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    7 |         scanf_s("%d",&n);
      |         ^~~~~~~
      |         scanf
Language: C

#include <stdio.h>

double slope(double x1, double x2, double y1, double y2) {
	printf("x1-x2 = %lf\n",x1-x2);
	printf("y1-y2 = %lf\n", y1 - y2);

	double slp = (x1 - x2) / (y1 - y2);
	return slp;
}

int main(void)
{
	int n;
	double x1[100], x2[100], x3[100], x4[100], y1[100], y2[100], y3[100], y4[100];
	int i = 0;
	double slope1, slope2;

	scanf_s("%d",&n);

	while (i < n) {
		scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1[i],&y1[i],&x2[i],&y2[i],&x3[i],&y3[i],&x4[i],&y4[i]);
		i++;
	}

	for (i = 0; i < n; i++) {
		slope1 = slope(x1[i],x2[i],y1[i],y2[i]);
		slope2 = slope(x3[i], x4[i], y3[i], y4[i]);

		printf("slope1 = %lf\n",slope1);

		printf("slope2 = %lf\n", slope2);


		if (slope1 == slope2) {
			printf("YES\n");
		}
		else {
			printf("NO\n");
		}
	}

	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:18:9: error: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
   18 |         scanf_s("%d",&n);
      |         ^~~~~~~
      |         scanf
Language: C

#include <cstdio>

int main( ) {
	int i, n;
	double x[4][100], y[4][100];
	double slope1[100], slope2[100];

	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		for (int j = 0; j < 4; j++) {
			scanf("%lf %lf", &x[j][i], &y[j][i]);
			slope1[i] = (y[1][i] - y[0][i]) / (x[1][i] - x[0][i]);
			slope2[i] = (y[3][i] - y[2][i]) / (x[3][i] - x[2][i]);
		}
	}

	for (i = 0; i < n; i++) {
		if (slope1[i] == slope2[i]) {
			printf("YES\n");
		}
		else {
			printf("NO\n");
		}
        }
	return 0;
}

Compiler output:
main.c:1:10: fatal error: cstdio: No such file or directory
    1 | #include <cstdio>
      |          ^~~~~~~~
compilation terminated.
Language: C

#include <stdio.h>

int main(void)
{
    int n;
    double x1, y1, x2, y2, x3, y3, x4, y4;
    double ax, ay, bx, by;
    double cross;

    scanf_s("%d", &n);

    while (n) {
        scanf_s("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
        ax = x2 - x1; 
        ay = y2 - y1;
        bx = x4 - x3;
        by = y4 - y3;

        cross = ax * by - ay * bx;
        printf("%lf\n", cross);
        if (cross == 0)
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:10:5: error: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
   10 |     scanf_s("%d", &n);
      |     ^~~~~~~
      |     scanf
Language: C

import java.io.*;
 
class Main{
    public static void main(String[] args){
    try{
        BufferedReader sc = new BufferedReader(new InputStreamReader(System.in));
        String st = sc.readLine();
        int n = Integer.valueOf(st);
        for(int i=0; i<n; i++){
        String[] pt = sc.readLine().split(" ");
        double[] a = new double[8];
        for(int j=0; j<8; j++)
            a[j] = Double.valueOf(pt[j]);
        if((a[3]-a[1])/(a[2]-a[0]) == (a[7]-a[5])/(a[6]-a[4]))
            System.out.println("YES");
        else
            System.out.println("NO");
        }
    }catch(Exception e){
        System.out.println("Error");
    }
    }
}

Compiler output:
main.c:1:1: error: unknown type name 'import'
    1 | import java.io.*;
      | ^~~~~~
main.c:1:12: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    1 | import java.io.*;
      |            ^
main.c:3:1: error: unknown type name 'class'
    3 | class Main{
      | ^~~~~
main.c:3:11: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
    3 | class Main{
      |           ^
Language: C

#include <stdio.h>

int main(void){
  int n, i;
  double x1, y1, x2, y2, x3, y3, x4, y4, k1, k2;
  scanf("%d", &n);
  for(i = 0; i < n; i ++){
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
    if(x2 - x1 == 0 && x3 - x4 == 0){
      printf("YES");
      continue;
    }
    else if(x2 - x1 == 0|| x3 - x4 == 0){
      prinf("NO");
      continue;
    }
    k1 = (y2 - y1) / (x2 - x1);
    k2 = (y4 - y3) / (x4 - x3);
    if(k1 == k2)
      printf("YES\n");
    else
      printf("NO\n");
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:14:7: error: implicit declaration of function 'prinf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   14 |       prinf("NO");
      |       ^~~~~
      |       printf
Language: C

#include <stdio.h>

int main(void){
  int n, i;
  double x1, y1, x2, y2, x3, y3, x4, y4, k1, k2;
  scanf("%d", &n);
  for(i = 0; i < n; i ++){
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
    if(x2 - x1 == 0 && x3 - x4 == 0){
      printf("YES\n");
      continue;
    }
    else if(x2 - x1 == 0|| x3 - x4 == 0){
      printf("NO\n");
      continue;
    }
    k1 = (y2 - y1) / (x2 - x1);
    k2 = (y4 - y3) / (x4 - x3);
    if(k1 == k2){
      if((y3 - y1) - k(x3 - x1) == 0)
	print("NO\n");
      else
      printf("YES\n");
    else
      printf("NO\n");
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:20:22: error: implicit declaration of function 'k' [-Wimplicit-function-declaration]
   20 |       if((y3 - y1) - k(x3 - x1) == 0)
      |                      ^
main.c:21:9: error: implicit declaration of function 'print'; did you mean 'printf'? [-Wimplicit-function-declaration]
   21 |         print("NO\n");
      |         ^~~~~
      |         printf
main.c:24:5: error: expected '}' before 'else'
   24 |     else
      |     ^~~~
Language: C

#include <stdio.h>

int main(void){
  int n, i;
  double x1, y1, x2, y2, x3, y3, x4, y4, k1, k2;
  scanf("%d", &n);
  for(i = 0; i < n; i ++){
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
    if(x2 - x1 == 0 && x3 - x4 == 0){
      printf("YES\n");
      continue;
    }
    else if(x2 - x1 == 0|| x3 - x4 == 0){
      printf("NO\n");
      continue;
    }
    k1 = (y2 - y1) / (x2 - x1);
    k2 = (y4 - y3) / (x4 - x3);
    if(k1 == k2){
      if((y3 - y1) - k(x3 - x1) == 0)
	print("NO\n");
      else
      printf("YES\n");
    }
    else
      printf("NO\n");
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:20:22: error: implicit declaration of function 'k' [-Wimplicit-function-declaration]
   20 |       if((y3 - y1) - k(x3 - x1) == 0)
      |                      ^
main.c:21:9: error: implicit declaration of function 'print'; did you mean 'printf'? [-Wimplicit-function-declaration]
   21 |         print("NO\n");
      |         ^~~~~
      |         printf
Language: C

#include <stdio.h>

int main(void){
  int n, i;
  double x1, y1, x2, y2, x3, y3, x4, y4, k1, k2;
  scanf("%d", &n);
  for(i = 0; i < n; i ++){
    scanf("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
    if(x1 == x2 && y1 == y2 || x3 == x4 && y3 = y4)
      printf("NO\n");
      else  if(x2 - x1 == 0 && x3 - x4 == 0){
      if(x2 == x4)
	printf("NO\n");
      else
      printf("YES\n");
      continue;
    }
    else if(x2 - x1 == 0|| x3 - x4 == 0){
      printf("NO\n");
      continue;
    }
    k1 = (y2 - y1) / (x2 - x1);
    k1 = (int) (k1*10000 +0.5) / 10000;
    k2 = (y4 - y3) / (x4 - x3);
    k2 = (int) (k2*10000 +0.5) / 10000;
    if(k1 == k2){
      if((y3 - y1) - k1*(x3 - x1) == 0)
	printf("NO\n");
      else
      printf("YES\n");
    }
    else
      printf("NO\n");
  }
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:9:47: error: lvalue required as left operand of assignment
    9 |     if(x1 == x2 && y1 == y2 || x3 == x4 && y3 = y4)
      |                                               ^
Language: C

#include <stdio.h>
int main(void){
    int n, i;
    double x[10], y[10], xy;
    scanf("%d" &n);
    for ( i = 0; i < n; i++) {
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x[1], &y[1], &x[2], &y[2], &x[3], &y[3], &x[4], &y[4]);
        if ( ( y[2] - y[1] ) / ( x[2] - x[1] ) ==  ( y[4] - y[3] ) / ( x[4] - x[3] ) ) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:5:16: error: invalid operands to binary & (have 'char *' and 'int')
    5 |     scanf("%d" &n);
      |           ~~~~ ^
      |           |
      |           char *
Language: C

#include<bits/stdc++.h>
using namespace std;
using ld=double;
const ld EPS=1e-6;
using Point=complex<ld>;

ld cross(Point a,Point b){
    return a.real()*b.imag()-a.imag()*b.real();
}

int main(){
    int n;
    cin>>n;
    for(int i=0;i<n;i++){
        vector<Point> xy(4);
        for(int i=0;i<4;i++){
            double x,y;
            cin>>x>>y;
            xy[i]=Point(x,y);
        }
        Point dir1=xy[1]-xy[0];
        Point dir2=xy[2]-xy[3];
        cout<<(abs(cross(dir1,dir2))<EPS ? "YES" : "NO")<<endl;
    
    }

    return 0;
}

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

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

int main( void )
{
    unsigned char i = 0;
    unsigned char num = 0;
    
    float x1,y1 = 0;
    float x2,y2 = 0;
    float x3,y3 = 0;
    float x4,y4 = 0;
    
    scanf("%d",&num);
    
    for(i=0; i<num; i++)
    {
        scanf("%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
        
        if( ( (x1-x2)/(y1-y2) ) == ( (x3-x4)/(y3-y4) ) )
        {
            printf("YES\n");
        }
        else
        {
            printf("NO\n");
        }
    }
　　
　　　
　　return 0;
}


Compiler output:
main.c: In function 'main':
main.c:29:1: error: stray '\343' in program
   29 | <U+3000><U+3000>
      | ^~~~~~~~
main.c:29:3: error: stray '\343' in program
   29 | <U+3000><U+3000>
      |         ^~~~~~~~
main.c:30:1: error: stray '\343' in program
   30 | <U+3000><U+3000><U+3000>
      | ^~~~~~~~
main.c:30:3: error: stray '\343' in program
   30 | <U+3000><U+3000><U+3000>
      |         ^~~~~~~~
main.c:30:5: error: stray '\343' in program
   30 | <U+3000><U+3000><U+3000>
      |                 ^~~~~~~~
main.c:31:1: error: stray '\343' in program
   31 | <U+3000><U+3000>return 0;
      | ^~~~~~~~
main.c:31:3: error: stray '\343' in program
   31 | <U+3000><U+3000>return 0;
      |         ^~~~~~~~
Language: C

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

int main( void )
{
    unsigned char i = 0;
    unsigned char num = 0;
    
    float x1,y1 = 0;
    float x2,y2 = 0;
    float x3,y3 = 0;
    float x4,y4 = 0;
    
    scanf("%d",&num);
    
    for(i=0; i<num; i++)
    {
        scanf("%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
        
        if( ( (x1-x2)/(y1-y2) ) == ( (x3-x4)/(y3-y4) ) )
        {
            printf("YES\n");
        }
        else
        {
            printf("NO\n");
        }
    }
　　
　　return 0;
}


Compiler output:
main.c: In function 'main':
main.c:29:1: error: stray '\343' in program
   29 | <U+3000><U+3000>
      | ^~~~~~~~
main.c:29:3: error: stray '\343' in program
   29 | <U+3000><U+3000>
      |         ^~~~~~~~
main.c:30:1: error: stray '\343' in program
   30 | <U+3000><U+3000>return 0;
      | ^~~~~~~~
main.c:30:3: error: stray '\343' in program
   30 | <U+3000><U+3000>return 0;
      |         ^~~~~~~~
Language: C

#include<stdio.h>

typedef struct point{
 double x;
 double y;
}point;

int main(){
 int n;
 point A,B,C,D;
 double m1,m2;
 scanf("%d",&n);
 for(i=0;i<n;i++){

  scanf("%lf %lf",&A.x,&A.y);
  scanf("%lf %lf",&B.x,&B.y);
  scanf("%lf %lf",&C.x,&C.y);
  scanf("%lf %lf",&D.x,&D.y);

  m1=(A.y-B.y)/(A.x-B.x);
  m2=(C.y-D.y)/(C.x-D.x);

  if(m1==m2)printf("YES\n");
  else printf("NO\n");

 }

 return 0;

}


Compiler output:
main.c: In function 'main':
main.c:13:6: error: 'i' undeclared (first use in this function)
   13 |  for(i=0;i<n;i++){
      |      ^
main.c:13:6: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    double a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(I=0;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        a = (y1-y2)/(x1-x2);
        b = (y3-y4)/(x3-x4);
        if(a == b)
        printf("YES\n");
       /* if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) == (y4-y3)/(x4-x3)){
            printf("YES\n");
        }else if((x1==x2) && (x3==x4)){
            printf("YES\n");
        }else if((x1==x2) || (x3==x4)){
            printf("NO\n");
        }else if((y1-y2)/(x1-x2) != (y3-y4)/(x3-x4))
            printf("NO\n");*/
            else if(a != b)
            printf("NO\n");
        
    }
    return 0;
}






Compiler output:
main.c: In function 'main':
main.c:11:9: error: 'I' undeclared (first use in this function)
   11 |     for(I=0;i<=j;i++){
      |         ^
main.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    int a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(i=1;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) != (y4-y3)/(x4-x3)){
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}






Compiler output:
main.c: In function 'main':
main.c:17:9: error: expected '}' before 'else'
   17 |         else
      |         ^~~~
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    int a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(i=1;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) != (y4-y3)/(x4-x3))
            printf("YES\n");
    
    return 0;
}






Compiler output:
main.c: In function 'main':
main.c:19:1: error: expected declaration or statement at end of input
   19 | }
      | ^
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    int a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(I=0;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);

        if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) == (y4-y3)/(x4-x3))
            printf("YES\n");
        else if((y1-y2)/(x1-x2) ==0 ||  (y3-y4)/(x3-x4)  ==0)
           printf("NO\n");
        else
            printf("NO\n");
    
    
    }
    return 0;
}





Compiler output:
main.c: In function 'main':
main.c:11:9: error: 'I' undeclared (first use in this function)
   11 |     for(I=0;i<=j;i++){
      |         ^
main.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    int a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(I=1;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);

        if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) == (y4-y3)/(x4-x3))
            printf("YES\n");
        else if((y1-y2)/(x1-x2) ==0 ||  (y3-y4)/(x3-x4)  ==0)
           printf("NO\n");
     //   else
      //      printf("NO\n");
    
    
    }
    return 0;
}





Compiler output:
main.c: In function 'main':
main.c:11:9: error: 'I' undeclared (first use in this function)
   11 |     for(I=1;i<=j;i++){
      |         ^
main.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    int a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(I=1;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);

        if((y1-y2)/(x1-x2) == (y3-y4)/(x3-x4))
            printf("YES\n");
        else if((y2-y1)/(x2-x1) == (y4-y3)/(x4-x3))
            printf("YES\n");
        else if((y1-y2)/(x1-x2) ==0 ||  (y3-y4)/(x3-x4)  ==0)
           printf("NO\n");
        else
            printf("NO\n");
    
    
    }
    return 0;
}





Compiler output:
main.c: In function 'main':
main.c:11:9: error: 'I' undeclared (first use in this function)
   11 |     for(I=1;i<=j;i++){
      |         ^
main.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void){
    int i,j;
    double a,b;
    double x1,y1;//A
    double x2,y2;//B
    double x3,y3;//C
    double x4,y4;//D

    scanf("%d",&j);
    for(I=0;i<=j;i++){
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        a = (y1-y2)/(x1-x2);
        b = (y3-y4)/(x3-x4);
       
        if(a == b)
            printf("YES\n");
        else if(a != b)
            printf("NO\n");
        else if(a == 0 && b == 0)
printf("YES\n");
    
    
    }
    return 0;
}



Compiler output:
main.c: In function 'main':
main.c:11:9: error: 'I' undeclared (first use in this function)
   11 |     for(I=0;i<=j;i++){
      |         ^
main.c:11:9: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
#include <math.h>

const double eps 1e-10;

int n;
double x1, x2, x3, x4;
double y1, y2, y3, y4;

//増加率を見る方法
int solve1() {
    double r1 = (y2-y1)/(x2-x1);
    double r2 = (y4-y3)/(x4-x3);
    return (fabs(r1-r2) < eps)
}

int main() {
    scanf("%d", &n);
    for(int i=0; i<n; ++i) {
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);

        if(solve1()) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }
}


Compiler output:
main.c:4:18: error: expected '=', ',', ';', 'asm' or '__attribute__' before numeric constant
    4 | const double eps 1e-10;
      |                  ^~~~~
main.c:8:8: error: 'y1' redeclared as different kind of symbol
    8 | double y1, y2, y3, y4;
      |        ^~
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/bits/libc-header-start.h:33,
                 from /usr/include/stdio.h:28,
                 from main.c:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:257:1: note: previous declaration of 'y1' with type 'double(double)'
  257 | __MATHCALL (y1,, (_Mdouble_));
      | ^~~~~~~~~~
main.c: In function 'solve1':
main.c:14:27: error: 'eps' undeclared (first use in this function)
   14 |     return (fabs(r1-r2) < eps)
      |                           ^~~
main.c:14:27: note: each undeclared identifier is reported only once for each function it appears in
main.c:14:31: error: expected ';' before '}' token
   14 |     return (fabs(r1-r2) < eps)
      |                               ^
      |                               ;
   15 | }
      | ~
Language: C

#include <stdio.h>
#include <math.h>

const double eps = 1e-10;

int n;
double x1, x2, x3, x4;
double y1, y2, y3, y4;

//増加率を見る方法
int solve1() {
    double r1 = (y2-y1)/(x2-x1);
    double r2 = (y4-y3)/(x4-x3);
    return (fabs(r1-r2) < eps);
}

int main() {
    scanf("%d", &n);
    for(int i=0; i<n; ++i) {
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);

        if(solve1()) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }
}


Compiler output:
main.c:8:8: error: 'y1' redeclared as different kind of symbol
    8 | double y1, y2, y3, y4;
      |        ^~
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/bits/libc-header-start.h:33,
                 from /usr/include/stdio.h:28,
                 from main.c:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:257:1: note: previous declaration of 'y1' with type 'double(double)'
  257 | __MATHCALL (y1,, (_Mdouble_));
      | ^~~~~~~~~~
Language: C

#include <stdio.h>
#include <math.h>

const double eps 1e-10;

int n;
//math.hライブラリでy1, y2...とかって変数名が使われてるらしい
double ix1, ix2, ix3, ix4;
double iy1, iy2, iy3, iy4;

//増加率を見る方法
int solve1() {
    double r1 = (iy2-y1)/(ix2-x1);
    double r2 = (iy4-y3)/(ix4-x3);
    return (fabs(r1-r2) < eps)
}

int main() {
    scanf("%d", &n);
    for(int i=0; i<n; ++i) {
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &ix1, &iy1, &ix2, &iy2, &ix3, &iy3, &ix4, &iy4);

        if(solve1()) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }
}


Compiler output:
main.c:4:18: error: expected '=', ',', ';', 'asm' or '__attribute__' before numeric constant
    4 | const double eps 1e-10;
      |                  ^~~~~
main.c: In function 'solve1':
main.c:13:21: error: invalid operands to binary - (have 'double' and 'double (*)(double)')
   13 |     double r1 = (iy2-y1)/(ix2-x1);
      |                     ^
      |                     |
      |                     double (*)(double)
main.c:13:31: error: 'x1' undeclared (first use in this function); did you mean 'r1'?
   13 |     double r1 = (iy2-y1)/(ix2-x1);
      |                               ^~
      |                               r1
main.c:13:31: note: each undeclared identifier is reported only once for each function it appears in
main.c:14:22: error: 'y3' undeclared (first use in this function); did you mean 'iy3'?
   14 |     double r2 = (iy4-y3)/(ix4-x3);
      |                      ^~
      |                      iy3
main.c:14:31: error: 'x3' undeclared (first use in this function); did you mean 'ix3'?
   14 |     double r2 = (iy4-y3)/(ix4-x3);
      |                               ^~
      |                               ix3
main.c:15:27: error: 'eps' undeclared (first use in this function)
   15 |     return (fabs(r1-r2) < eps)
      |                           ^~~
main.c:15:31: error: expected ';' before '}' token
   15 |     return (fabs(r1-r2) < eps)
      |                               ^
      |                               ;
   16 | }
      | ~
Language: C

#include <stdio.h>
#include <math.h>

const double eps = 1e-10;

int n;
//math.hライブラリでy1, y2...とかって変数名が使われてるらしい
double ix1, ix2, ix3, ix4;
double iy1, iy2, iy3, iy4;

//増加率を見る方法
int solve1() {
    double r1 = (iy2-y1)/(ix2-x1);
    double r2 = (iy4-y3)/(ix4-x3);
    return (fabs(r1-r2) < eps)
}

int main() {
    scanf("%d", &n);
    for(int i=0; i<n; ++i) {
        scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &ix1, &iy1, &ix2, &iy2, &ix3, &iy3, &ix4, &iy4);

        if(solve1()) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }
}


Compiler output:
main.c: In function 'solve1':
main.c:13:21: error: invalid operands to binary - (have 'double' and 'double (*)(double)')
   13 |     double r1 = (iy2-y1)/(ix2-x1);
      |                     ^
      |                     |
      |                     double (*)(double)
main.c:13:31: error: 'x1' undeclared (first use in this function); did you mean 'r1'?
   13 |     double r1 = (iy2-y1)/(ix2-x1);
      |                               ^~
      |                               r1
main.c:13:31: note: each undeclared identifier is reported only once for each function it appears in
main.c:14:22: error: 'y3' undeclared (first use in this function); did you mean 'iy3'?
   14 |     double r2 = (iy4-y3)/(ix4-x3);
      |                      ^~
      |                      iy3
main.c:14:31: error: 'x3' undeclared (first use in this function); did you mean 'ix3'?
   14 |     double r2 = (iy4-y3)/(ix4-x3);
      |                               ^~
      |                               ix3
main.c:15:31: error: expected ';' before '}' token
   15 |     return (fabs(r1-r2) < eps)
      |                               ^
      |                               ;
   16 | }
      | ~
Language: C

#include<stdio.h>
 
int main(){
  int n;
  double x1,x2,x3,x4,y1,y2,y3,y4,m1,m2;
 
  scanf("%d",&n);
 
  while(n-- > 0){
    scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
    m1 = (y2-y1)/(x2-x1);
    m2 = (y4-y3)/(x4-x3);
    if(m1 == m2)printf("YES\n"):printf("NO\n");
  }
}


Compiler output:
main.c: In function 'main':
main.c:13:32: error: expected ';' before ':' token
   13 |     if(m1 == m2)printf("YES\n"):printf("NO\n");
      |                                ^
      |                                ;
Language: C

#include<stdio.h>


int main(void){
int a,i;
double x[4],y[4];
double b[100],c[100];

scanf("%d",&a);
for(i = 1; i <= a; i++){
  scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x[0],&[0]1,&x[1],&y[1],&x[2],&y[2],&x[3],&y[3]);
}
b[i] = (y[1] - y[0])/(x[1] - x[0]);
c[i] = (y[3] - y[2])/(x[3] - x[2]);

for(i = 1; i <= a; i++){
  if(b[i] == c[i]){
   printf("YES\n");
  }
  else{
  printf("NO\n");
  }
}
return 0;

}


Compiler output:
main.c: In function 'main':
main.c:11:50: error: expected expression before '[' token
   11 |   scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x[0],&[0]1,&x[1],&y[1],&x[2],&y[2],&x[3],&y[3]);
      |                                                  ^
Language: C

#include<stdio.h>


int main(void){
int a,i;
double x[4],y[4],b,c;

scanf("%d",&a);
for(i = 1; i <= a; i++){
  scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x[0],&y[0],&x[1],&y[1],&x[2],&y[2],&x[3],&y[3]);

b = (y[1] - y[0])/(x[1] - x[0]);
c = (y[3] - y[2])/(x[3] - x[2]);


  if(b == c)
   printf("YES\n");
  
  else
  printf("NO\n");
  
}
return 0;




Compiler output:
main.c: In function 'main':
main.c:23:1: error: expected declaration or statement at end of input
   23 | return 0;
      | ^~~~~~
Language: C

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

	int n, i;
	double x1, x2, x3, x4, y1, y2, y3, y4;

	scanf("%d",n);
	for(i=0; i<n; i++){
		scanf("%lf %lf %lf %lf %lf %lf %lf %lf %lf %lf",x1, y1, x2, y2, x3, y3, x4, y4);
		ab = (y2 - y1) / (x2 - x1);
		cd = (y4 - y3) / (x4 - x3);
		
		if( ab == cd ){
			printf("YES\n");
		}else{
		 	printf("NO\n");
		}
	}
		
	return 0;

}


Compiler output:
main.c: In function 'main':
main.c:10:17: error: 'ab' undeclared (first use in this function)
   10 |                 ab = (y2 - y1) / (x2 - x1);
      |                 ^~
main.c:10:17: note: each undeclared identifier is reported only once for each function it appears in
main.c:11:17: error: 'cd' undeclared (first use in this function)
   11 |                 cd = (y4 - y3) / (x4 - x3);
      |                 ^~
Language: C

# AOJ 0021: Parallelism
# Python3 2018.6.15 bal4u

EPS = 1e-7

def EQ(a, b):
	return True if abs(a - b) < EPS else False
	
n = int(input())
for i in range(n):
	ax1, ay1, ax2, ay2, bx1, by1, bx2, by2 = list(map(float, input().split()))
	f = False
	if EQ(ax1, ax2) and EQ(bx1, bx2): f = True
	elif EQ((ay2-ay1)*(bx2-bx1), (ax2-ax1)*(by2-by1)): f = True
	print('YES' if f else 'NO')




Compiler output:
main.c:1:3: error: invalid preprocessing directive #AOJ
    1 | # AOJ 0021: Parallelism
      |   ^~~
main.c:2:3: error: invalid preprocessing directive #Python3
    2 | # Python3 2018.6.15 bal4u
      |   ^~~~~~~
main.c:4:1: warning: data definition has no type or storage class
    4 | EPS = 1e-7
      | ^~~
main.c:4:1: error: type defaults to 'int' in declaration of 'EPS' [-Wimplicit-int]
main.c:6:1: error: expected ',' or ';' before 'def'
    6 | def EQ(a, b):
      | ^~~
main.c:15:15: warning: multi-character character constant [-Wmultichar]
   15 |         print('YES' if f else 'NO')
      |               ^~~~~
main.c:15:31: warning: multi-character character constant [-Wmultichar]
   15 |         print('YES' if f else 'NO')
      |                               ^~~~
Language: C

#include <stdio.h>
int main(void){
    int i,n;
    double x1,x2,x3,x4,y1,y2,y3,y4,AB,CD;
    scanf("%d",&n);
    for(i=0;i<n;i++){
        scanf("%d %d %d %d %d %d %d %d",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        AB=(x2-x1)/(y2-y1);
        CD=(x4-x3)/(y4-y3);
        if(AB==CD)
        puts("YES");
        else
        puts("NO")
    }
    return 0;
}



Compiler output:
main.c: In function 'main':
main.c:13:19: error: expected ';' before '}' token
   13 |         puts("NO")
      |                   ^
      |                   ;
   14 |     }
      |     ~
Language: C

#include <stdio.h>
int main(void){
double x1, y1, x2, y2, x3, y3, x4, y4;
double a1,a2,b1,b2;
double c1,c2;
int n;
int i;

scanf("%d",&n);
for(i=0;i<n;i++){
     scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
     a1=x2-x1;
     a2=x4-x3;
     b1=y2-y1;
     b2=y4-y3;
     
     c1=b1/a1;
     c2=b2/a2;
     if(c1==c2){
         printf("YES\n");
     }else{
         printf("NO\n");
     }
}


Compiler output:
main.c: In function 'main':
main.c:24:1: error: expected declaration or statement at end of input
   24 | }
      | ^
Language: C

#include<stdio.h>
int main(){
int i,n;
double a[2],b[2],c[2],d[2];
scanf("%d",&n);
for(i=0;i<n;i++){
scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&a[0],&a[1],&b[0],&b[1],&c[0],&c[1],&d[0],&d[1]);
if((b[1]-a[1])*(d[0]-c[0])==(b[0]-a[0])(d[1]-c[1]))
printf("YES\n");
else
printf("NO\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:34: error: called object is not a function or function pointer
    8 | if((b[1]-a[1])*(d[0]-c[0])==(b[0]-a[0])(d[1]-c[1]))
      |                             ~~~~~^~~~~~
Language: C

#include<stdio.h>
int main()
{
	int a,i,j[100000];
	float x1,y1,x2,y2,x3,y3,x4,y4;
	for(a=0;a<100;a++)
	{
		j[a]=0;
	}
	scanf("%d",&a);
	for(i=0;i<a;i++)
	{
		scanf("%f%f%f%f%f%f%f%f",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
		if(((x1-x2)/(x3-x4))--((y1-y2)/(y3-y4)))
			j[i]=1;		
		
	}
	for(i=0;i<a;i++)
	{
		if(j[i]==0)
			printf("NO\n");
		else
			printf("YES\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:14:37: error: lvalue required as decrement operand
   14 |                 if(((x1-x2)/(x3-x4))--((y1-y2)/(y3-y4)))
      |                                     ^~
Language: C

#include<stdio.h>
int main()
{
	int a,i,j[100000];
	float x1,y1,x2,y2,x3,y3,x4,y4;
	for(a=0;a<100;a++)
	{
		j[a]=0;
	}
	scanf("%d",&a);
	for(i=0;i<a;i++)
	{
		scanf("%f%f%f%f%f%f%f%f",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
		if((x1-x2)/(x3-x4))!=((x1-x3)/(y1-y3))&&((x1-x2)/(x3-x4))==((y1-y2)/(y3-y4)))
			j[i]=1;		
		
	}
	for(i=0;i<a;i++)
	{
		if(j[i]==0)
			printf("NO\n");
		else
			printf("YES\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:14:36: error: expected expression before '!=' token
   14 |                 if((x1-x2)/(x3-x4))!=((x1-x3)/(y1-y3))&&((x1-x2)/(x3-x4))==((y1-y2)/(y3-y4)))
      |                                    ^~
main.c:14:93: error: expected statement before ')' token
   14 |                 if((x1-x2)/(x3-x4))!=((x1-x3)/(y1-y3))&&((x1-x2)/(x3-x4))==((y1-y2)/(y3-y4)))
      |                                                                                             ^
Language: C

#include <stdio.h>

int main(){
  int setcount;
  double x1, y1, x2, y2, x3, y3, x4, y4;
  double r1, r2;
  int i;

  scanf("%d", &setcount);
  for(i=0; i<setcount; i++){
    scanf(%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
    r1=(y2-y1)/(x2-x1);
    r2=(y4-y3)/(x4-x3);
    if(r1==r2) printf("YES\n");
    else printf("NO\n");
  }

  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:11: error: expected expression before '%' token
   11 |     scanf(%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
      |           ^
main.c:11:34: warning: missing terminating " character
   11 |     scanf(%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
      |                                  ^
main.c:11:34: error: missing terminating " character
   11 |     scanf(%f %f %f %f %f %f %f %f", &x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4);
      |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:15:25: error: expected ';' before '}' token
   15 |     else printf("NO\n");
      |                         ^
      |                         ;
   16 |   }
      |   ~