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

#include <stdio.h>
int main(void)
{
char x[2] = {#, .};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

for(; W > i; i++)
printf("%c",x[i % 2]);

printf("\n")
i++;
}
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:4:14: error: stray '#' in program
    4 | char x[2] = {#, .};
      |              ^
main.c:4:15: error: expected expression before ',' token
    4 | char x[2] = {#, .};
      |               ^
main.c:20:13: error: expected ';' before 'i'
   20 | printf("\n")
      |             ^
      |             ;
   21 | i++;
      | ~
Language: C

#include <stdio.h>
int main(void)
{
char x[2] = {'#', '.'};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

for(; W > i; i++)
printf("%c",x[i % 2]);

printf("\n")
i++;
}
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:20:13: error: expected ';' before 'i'
   20 | printf("\n")
      |             ^
      |             ;
   21 | i++;
      | ~
Language: C

#include <stdio.h>
int main(void)
{
char x[2] = {"#", "."};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

whle(W > i){
printf("%s",x[i % 2]);
i++;
}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:4:19: error: excess elements in 'char[2]' initializer
    4 | char x[2] = {"#", "."};
      |                   ^~~
main.c:4:19: note: (near initialization for 'x')
main.c:17:1: error: implicit declaration of function 'whle' [-Wimplicit-function-declaration]
   17 | whle(W > i){
      | ^~~~
main.c:17:12: error: expected ';' before '{' token
   17 | whle(W > i){
      |            ^
      |            ;
Language: C

#include <stdio.h>
int main(void)
{
char x[2] = {'#', '.'};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

whle(W > i){
printf("%s",x[i % 2]);
i++;
}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:17:1: error: implicit declaration of function 'whle' [-Wimplicit-function-declaration]
   17 | whle(W > i){
      | ^~~~
main.c:17:12: error: expected ';' before '{' token
   17 | whle(W > i){
      |            ^
      |            ;
Language: C

#include <stdio.h>
int main(void)
{
char x[2] = {'#', '.'};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

whle(W > i){
printf("%c",x[i % 2]);
i++;
}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:17:1: error: implicit declaration of function 'whle' [-Wimplicit-function-declaration]
   17 | whle(W > i){
      | ^~~~
main.c:17:12: error: expected ';' before '{' token
   17 | whle(W > i){
      |            ^
      |            ;
Language: C

#include <stdio.h>
int main(void)
{
char x[2] = {'#', '.'};
int W, H, i, j;

while(1) {

scanf("%d %d",&H,&W);

if(H == 0 && W == 0)
   break;

i = 0;
for(j = 0; H > j; j++){

whle(W > i){
printf("%c", x[i % 2]);
i++;
}
i++;
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:17:1: error: implicit declaration of function 'whle' [-Wimplicit-function-declaration]
   17 | whle(W > i){
      | ^~~~
main.c:17:12: error: expected ';' before '{' token
   17 | whle(W > i){
      |            ^
      |            ;
Language: C

#include <stdio.h>
int main(void)
{
int i,j;
int H,W;

while(1){
 scanf("%d %d,&H,&W);
 if ( H == 0 && W == 0 )
  break ;

 for(i=0;i<H;i++){
  for(j=0;j<W;j++){
   if((i+j)%2==0)
    printf("#");
   else if((i+j)%2==1)
    printf(".")
   }
   printf("\n");
 }
 printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:8: warning: missing terminating " character
    8 |  scanf("%d %d,&H,&W);
      |        ^
main.c:8:8: error: missing terminating " character
    8 |  scanf("%d %d,&H,&W);
      |        ^~~~~~~~~~~~~~
main.c:9:2: error: expected expression before 'if'
    9 |  if ( H == 0 && W == 0 )
      |  ^~
main.c:21:15: error: expected ';' before '}' token
   21 |  printf("\n");
      |               ^
      |               ;
   22 | }
      | ~
Language: C

#include<stdio.h>

int main(){

  char a = '#';
  char A = '.';
  int i,j;
  int b[300][300];
  int x,y;
  
  while(1){
    scanf("%d%d",&x,&y);
  
  if (x ==0 && y ==0){
    break;
  }
    
  for(i=0;i<x;i++){
    for(j=0;j<y;j++){
      
      if(i%2==1 && j%2==1 || i%2==0 && j%2==0) printf("%c",a);
      else printf("%c",A);
      
    }printf("\n");
  }
  printf("\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 (void) {

	int x, y;
	int i, j;

	while (1) {
		if (x+y == 0)
			break;
		scanf ("%d %d", &y, &x);
		for (j=0; j<y; j++) {
			for (i=0; i<x; i++) {
				if (j%2==0) {
					if (i%2==0)
						printf("#");
					if (i%2==1)
						printf(".");
				} else {
					if (i%2==0)
						printf(".");
					if (i%2==1)
						printf("#");
				}
			}
		printf("\n");
		}
		if (x+y=0)
			printf("\n");
	}

	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:28:24: error: lvalue required as left operand of assignment
   28 |                 if (x+y=0)
      |                        ^
Language: C

#include <stdio.h>
main()
{
	int H, W, i,j;

	while(1){
		scanf("%d %d", &H, &W);
		if(H == 0 && W == 0) break;
		
		for(i = 1; i <= H; i++){
			if(i % 2 != 0){
				for(j = 1; j <= W; j++){
					if(j % 2 != 0){
						printf("#");
					}else{
						printf(".");
					}
				}
			}else{
				for(j = 1; j <= W; j++){
					if(j % 2 != 0){
						printf(".");
					}else{
						printf("#");
					}
				}
			}
			printf("\n");
		}
		printf("\n");
	}

Compiler output:
main.c:2:1: error: return type defaults to 'int' [-Wimplicit-int]
    2 | main()
      | ^~~~
main.c: In function 'main':
main.c:31:9: error: expected declaration or statement at end of input
   31 |         }
      |         ^
Language: C

include<stdio.h>
  
int main(){
 while(1){
  int H,W;
  scanf("%d%d", &H,&W);
  if(H==0 && W==0){break;}
  int i,j;
  for(i=0; i<H; i++){
   for(j=0; j<W; j++){
    if(i%2==0 && j%2==0){printf("#");}
    else if(i%2==0 && j%2==0){printf("#");}
    else if(i%2!=0 && j%2==0){printf(".");}
    else if(i%2==0 && j%2!=0){printf(".");}
    else if(i%2!=0 && j%2!=0){printf("#");}
}
   printf("\n");
  }
  printf("\n");
 }
 return 0;
}

Compiler output:
main.c:1:8: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
    1 | include<stdio.h>
      |        ^
Language: C

#include<stdio.h>
int main(){
int h,w,i,j,k,l;
while(1){
scanf("%d %d",&h,&w);
if((h==0)&&(w==0)) break;
if(w%2!=0) l = 1;
for(i==0;i<h;i++){

for(j==0;j<w;w++){
if(i==0 && j==0 ) k=0;//k=0??????#
if(k==0){
printf("#")
k=1;
}else{
printf(".");
k=0;
}
if(l==1){
if(k=0)k=1;else k=0;
}

}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:13:12: error: expected ';' before 'k'
   13 | printf("#")
      |            ^
      |            ;
   14 | k=1;
      | ~
Language: C

#include<stdio.h>
int main(){
int h,w,i,j,k,l;
while(1){
scanf("%d %d",&h,&w);
if((h==0)&&(w==0)) break;
if(w%2!=0) l = 1;
for(i==0;i<h;i++){

for(j==0;j<w;w++){
if(i==0 && j==0 ) k=0;//k=0??????#
if(k==0){
printf("#")
k=1;
}else{
printf(".");
k=0;
}
if(l==1){
if(k==0)k=1;else k=0;
}

}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:13:12: error: expected ';' before 'k'
   13 | printf("#")
      |            ^
      |            ;
   14 | k=1;
      | ~
Language: C

#include<stdio.h>
int main(){
int h,w,i,j,k,l;
while(1){
scanf("%d %d",&h,&w);
if((h==0)&&(w==0)) break;
if(w%2!=0) l = 1;
for(i==0;i<h;i++){

for(j==0;j<w;w++){ 
if(i==0 && j==0) k=0;//k=0??????#
if(k==0){
printf("#")
k=1;
}else{
printf(".");
k=0;
}
if(l==1){
if(k==0)k=1;else k=0;
} 
}
printf("\n");
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:13:12: error: expected ';' before 'k'
   13 | printf("#")
      |            ^
      |            ;
   14 | k=1;
      | ~
Language: C

#include<stdio.h>

int main(){

int h,w,i,j;

while(1){

scanf("%d %d",h,w);

if(h==0 && w==0)break;

for(i=0;i<=h;i++){
if((i%2==0)||i==0){
for(j=0;j<=w;j++){
if((i%2==0)||i==0){
printf("#");
}else{
printf(".");
}

}
}else{
for(j=0;j<=w;j++){
if((i%2==0)||i==0){
printf("#");
}else{
printf(".");
}


}
printf("\n");
}


return 0;
}

Compiler output:
main.c: In function 'main':
main.c:38:1: error: expected declaration or statement at end of input
   38 | }
      | ^
main.c:38:1: error: expected declaration or statement at end of input
Language: C

#include<stdio.h>

int main(){

int h,w,i,j;

while(1){

scanf("%d %d",h,w);

if(h==0 && w==0)break;

for(i=0;i<=h;i++){
if((i%2==0)||i==0){
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}

}
}else{
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}


}
printf("\n");
}
printf("\n);
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:35:8: warning: missing terminating " character
   35 | printf("\n);
      |        ^
main.c:35:8: error: missing terminating " character
   35 | printf("\n);
      |        ^~~~~
main.c:36:1: error: expected expression before '}' token
   36 | }
      | ^
main.c:35:8: error: expected ';' before '}' token
   35 | printf("\n);
      |        ^
      |        ;
   36 | }
      | ~       
main.c:38:1: error: expected declaration or statement at end of input
   38 | }
      | ^
Language: C

#include<stdio.h>

int main(){

int h,w,i,j;

while(1){

scanf("%d %d",h,w);

if(h==0 && w==0)break;

for(i=0;i<=h;i++){
if((i%2==0)||i==0){
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}
}
}
}else{
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}

}
}
printf("\n");
}
printf("\n);
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:23:2: error: 'else' without a previous 'if'
   23 | }else{
      |  ^~~~
main.c:35:8: warning: missing terminating " character
   35 | printf("\n);
      |        ^
main.c:35:8: error: missing terminating " character
   35 | printf("\n);
      |        ^~~~~
main.c:36:1: error: expected expression before '}' token
   36 | }
      | ^
main.c:35:8: error: expected ';' before '}' token
   35 | printf("\n);
      |        ^
      |        ;
   36 | }
      | ~       
main.c: At top level:
main.c:37:1: error: expected identifier or '(' before 'return'
   37 | return 0;
      | ^~~~~~
main.c:38:1: error: expected identifier or '(' before '}' token
   38 | }
      | ^
Language: C

#include<stdio.h>

int main(){

int h,w,i,j;

while(1){//?????????????§?

scanf("%d %d",h,w);

if(h==0 && w==0)break;

for(i=0;i<=h;i++){//i?????????
if((i%2==0)||i==0){
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}
}

}else{
for(j=0;j<=w;j++){
if((j%2==0)||j==0){
printf("#");
}else{
printf(".");
}

}
}
printf("\n");
}//i?????????
printf("\n);
}//???????????????
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:35:8: warning: missing terminating " character
   35 | printf("\n);
      |        ^
main.c:35:8: error: missing terminating " character
   35 | printf("\n);
      |        ^~~~~
main.c:36:1: error: expected expression before '}' token
   36 | }//???????????????
      | ^
main.c:35:8: error: expected ';' before '}' token
   35 | printf("\n);
      |        ^
      |        ;
   36 | }//???????????????
      | ~
Language: C

#include<stdio.h>
int main(){
int h,w,i,j,a;
while(1){
a=0;
scanf("%d %d",&h,&w);
if(w%2==0)b=1;else b=0;
if((h==0)&&(w==0))break;
for(i=0;i<h;i++){
for(j=0;j<w;j++){

if(a==0){
printf("#"); 
a=1;
}else{
printf(".");
a=0;
}

}
printf("\n");
if(b==1){
if(a==0)a=1;else a=0;
}
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:7:11: error: 'b' undeclared (first use in this function)
    7 | if(w%2==0)b=1;else b=0;
      |           ^
main.c:7:11: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include <stdio.h>
int main(void) {
    int H, W, i, j;
    while (scanf("%d %d", &H, &W) == 2) {
        char pattern[W];
        if (H == 0 && W == 0) break;
        for (i = 0; i <= W / 2; i ++) {
            pattern[2i] = '#';
            pattern[2i + 1] = '.';
        }
        for (j = 0; j <= H - 1; j ++) {
            if (j % 2 == 0) {
                for (i = 0; i <= W - 1; i ++) printf("%c", pattern[i]);
                print("\n");
            }
            if (j % 2 == 1) {
                for (i = W - 1; i >= 0; i --) printf("%c", pattern[i]);
                printf("\n");
            }
        }
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:20: error: array subscript is not an integer
    8 |             pattern[2i] = '#';
      |                    ^
main.c:9:20: error: array subscript is not an integer
    9 |             pattern[2i + 1] = '.';
      |                    ^
main.c:14:17: error: implicit declaration of function 'print'; did you mean 'printf'? [-Wimplicit-function-declaration]
   14 |                 print("\n");
      |                 ^~~~~
      |                 printf
Language: C

#include <stdio.h>
int main(void) {
    int H, W, i, j;
    while (scanf("%d %d", &H, &W) == 2) {
        char pattern[W];
        if (H == 0 && W == 0) break;
        for (i = 0; i <= W / 2; i ++) {
            pattern[2i] = '#';
            pattern[2i + 1] = '.';
        }
        for (j = 0; j <= H - 1; j ++) {
            if (j % 2 == 0) {
                for (i = 0; i <= W - 1; i ++) printf("%c", pattern[i]);
                printf("\n");
            }
            if (j % 2 == 1) {
                for (i = W - 1; i >= 0; i --) printf("%c", pattern[i]);
                printf("\n");
            }
        }
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:20: error: array subscript is not an integer
    8 |             pattern[2i] = '#';
      |                    ^
main.c:9:20: error: array subscript is not an integer
    9 |             pattern[2i + 1] = '.';
      |                    ^
Language: C

#include <stdio.h>
int main(void) {
    int H, W, i, j;
    while (scanf("%d %d", &H, &W) == 2) {
        int pattern[W];
        if (H == 0 && W == 0) break;
        for (i = 0; i <= W / 2; i ++) {
            pattern[2i] = '#';
            pattern[2i + 1] = '.';
        }
        for (j = 0; j <= H - 1; j ++) {
            if (j % 2 == 0) {
                for (i = 0; i <= W - 1; i ++) printf("%c", pattern[i]);
                printf("\n");
            }
            if (j % 2 == 1) {
                for (i = W - 1; i >= 0; i --) printf("%c", pattern[i]);
                printf("\n");
            }
        }
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:8:20: error: array subscript is not an integer
    8 |             pattern[2i] = '#';
      |                    ^
main.c:9:20: error: array subscript is not an integer
    9 |             pattern[2i + 1] = '.';
      |                    ^
Language: C

#include <stdio.h>
#include <math.h>
int main(){
	int H,W,i,j,cnt=0;
	while(1){
		cnt=0
	scanf("%d %d",&H,&W);
		if(H ==0 && W==0){
			break;
		}
		for (i = 0; i < H; i++)
		{
			for (j = 0; j < W; j++)
			{
				if(cnt%2==0){
					printf("#");
				}else{
					printf(".");
				}
				cnt++;
			}
			cnt++;
			printf("\n");
		}
			printf("\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:6:22: error: expected ';' before 'scanf'
    6 |                 cnt=0
      |                      ^
      |                      ;
    7 |         scanf("%d %d",&H,&W);
      |         ~~~~~
Language: C

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

 int H, W, i, j;

 while(1) {
 scanf("%d%d",&H,&W);
 if(H == 0 && W == 0) break;
  for(i = 1; i <= H; i++) {
   for(j = 1; j <= W; j++) {
    if((i+j)%2 == 0) {
    printf("#");
    } else {
    printf(".");
    }
  printf("\n");
  }
 printf("\n");
 }

 return 0;
}

Compiler output:
main.c: In function 'main':
main.c:22:1: error: expected declaration or statement at end of input
   22 | }
      | ^
Language: C

#include <stdio.h>

int main(void) {
	int H, W, k, l, p;
	
	while(1){
		scanf("%d %d", &H, &W);
		for(l=0;l<H;l++);{
			for(p=0;p<W;p++){
			k= l+p+2,
			if(k%2 == 0) printf("#");
			else printf(".");
			
			}
			
			
			
			printf("\n");
		}
		
	}
	
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:25: error: expected expression before 'if'
   11 |                         if(k%2 == 0) printf("#");
      |                         ^~
main.c:12:25: error: 'else' without a previous 'if'
   12 |                         else printf(".");
      |                         ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
boolean flagx = false;
boolean flagy = false;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
for (y = 0; y < H; y++) {
if (flagy == 0) {
flagy = true;
} else {
flagy = true;
}
for (x = 0; x < W; x++) {
if (x == 0) {
if (flagy) {
printf("#");
flagy = false;
flagx = false;
} else {
printf(".");
flagy = true;
flagx = false;
}
} else {
if (flagx) [
pritnf("#");
flagx = false;
} else {
printf(".");
flagx = true;
}
}
}
printf("\n");
}
printf("\n");

return (0);
}

Compiler output:
main.c: In function 'main':
main.c:6:1: error: unknown type name 'boolean'
    6 | boolean flagx = false;
      | ^~~~~~~
main.c:6:17: error: 'false' undeclared (first use in this function)
    6 | boolean flagx = false;
      |                 ^~~~~
main.c:2:1: note: 'false' 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:6:17: note: each undeclared identifier is reported only once for each function it appears in
    6 | boolean flagx = false;
      |                 ^~~~~
main.c:7:1: error: unknown type name 'boolean'
    7 | boolean flagy = false;
      | ^~~~~~~
main.c:12:9: error: 'true' undeclared (first use in this function)
   12 | flagy = true;
      |         ^~~~
main.c:12:9: note: 'true' is defined in header '<stdbool.h>'; this is probably fixable by adding '#include <stdbool.h>'
main.c:28:12: error: expected expression before '[' token
   28 | if (flagx) [
      |            ^
main.c:29:1: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 | pritnf("#");
      | ^~~~~~
      | printf
main.c:30:15: error: expected ';' before '}' token
   30 | flagx = false;
      |               ^
      |               ;
   31 | } else {
      | ~              
main.c:31:3: error: 'else' without a previous 'if'
   31 | } else {
      |   ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
bool flagx = false;
bool flagy = false;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
for (y = 0; y < H; y++) {
if (flagy == 0) {
flagy = true;
} else {
flagy = true;
}
for (x = 0; x < W; x++) {
if (x == 0) {
if (flagy) {
printf("#");
flagy = false;
flagx = false;
} else {
printf(".");
flagy = true;
flagx = false;
}
} else {
if (flagx) [
pritnf("#");
flagx = false;
} else {
printf(".");
flagx = true;
}
}
}
printf("\n");
}
printf("\n");

return (0);
}

Compiler output:
main.c: In function 'main':
main.c:6:1: error: unknown type name 'bool'
    6 | bool flagx = false;
      | ^~~~
main.c:2:1: note: 'bool' 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:6:14: error: 'false' undeclared (first use in this function)
    6 | bool flagx = false;
      |              ^~~~~
main.c:6:14: note: 'false' is defined in header '<stdbool.h>'; this is probably fixable by adding '#include <stdbool.h>'
main.c:6:14: note: each undeclared identifier is reported only once for each function it appears in
main.c:7:1: error: unknown type name 'bool'
    7 | bool flagy = false;
      | ^~~~
main.c:7:1: note: 'bool' is defined in header '<stdbool.h>'; this is probably fixable by adding '#include <stdbool.h>'
main.c:12:9: error: 'true' undeclared (first use in this function)
   12 | flagy = true;
      |         ^~~~
main.c:12:9: note: 'true' is defined in header '<stdbool.h>'; this is probably fixable by adding '#include <stdbool.h>'
main.c:28:12: error: expected expression before '[' token
   28 | if (flagx) [
      |            ^
main.c:29:1: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 | pritnf("#");
      | ^~~~~~
      | printf
main.c:30:15: error: expected ';' before '}' token
   30 | flagx = false;
      |               ^
      |               ;
   31 | } else {
      | ~              
main.c:31:3: error: 'else' without a previous 'if'
   31 | } else {
      |   ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
for (y = 0; y < H; y++) {
if (flagy == 0) {
flagy = 1;
} else {
flagy = 0;
}
for (x = 0; x < W; x++) {
if (x == 0) {
if (flagy == 1) {
printf("#");
flagy = 0;
flagx = 0;
} else {
printf(".");
flagy = 1;
flagx = 1;
}
} else {
if (flagx == 1) [
pritnf("#");
flagx = 0;
} else {
printf(".");
flagx = 1;
}
}
}
printf("\n");
}
printf("\n");

return (0);
}

Compiler output:
main.c: In function 'main':
main.c:28:17: error: expected expression before '[' token
   28 | if (flagx == 1) [
      |                 ^
main.c:29:1: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 | pritnf("#");
      | ^~~~~~
      | printf
main.c:30:11: error: expected ';' before '}' token
   30 | flagx = 0;
      |           ^
      |           ;
   31 | } else {
      | ~          
main.c:31:3: error: 'else' without a previous 'if'
   31 | } else {
      |   ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1) [
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");

  return (0);
}

Compiler output:
main.c: In function 'main':
main.c:28:25: error: expected expression before '[' token
   28 |         if (flagx == 1) [
      |                         ^
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
main.c:30:21: error: expected ';' before '}' token
   30 |           flagx = 0;
      |                     ^
      |                     ;
   31 |         } else {
      |         ~            
main.c:31:11: error: 'else' without a previous 'if'
   31 |         } else {
      |           ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1) [
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");
}
  return (0);
}

Compiler output:
main.c: In function 'main':
main.c:28:25: error: expected expression before '[' token
   28 |         if (flagx == 1) [
      |                         ^
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
main.c:30:21: error: expected ';' before '}' token
   30 |           flagx = 0;
      |                     ^
      |                     ;
   31 |         } else {
      |         ~            
main.c:31:11: error: 'else' without a previous 'if'
   31 |         } else {
      |           ^~~~
main.c: At top level:
main.c:41:3: error: expected identifier or '(' before 'return'
   41 |   return (0);
      |   ^~~~~~
main.c:42:1: error: expected identifier or '(' before '}' token
   42 | }
      | ^
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1)
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");

  return (0);
}

Compiler output:
main.c: In function 'main':
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
main.c:31:11: error: 'else' without a previous 'if'
   31 |         } else {
      |           ^~~~
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1)
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");
}
  return (0);
}

Compiler output:
main.c: In function 'main':
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
main.c:31:11: error: 'else' without a previous 'if'
   31 |         } else {
      |           ^~~~
main.c: At top level:
main.c:41:3: error: expected identifier or '(' before 'return'
   41 |   return (0);
      |   ^~~~~~
main.c:42:1: error: expected identifier or '(' before '}' token
   42 | }
      | ^
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1)
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");
}
  return (0);
}
}

Compiler output:
main.c: In function 'main':
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
main.c:31:11: error: 'else' without a previous 'if'
   31 |         } else {
      |           ^~~~
main.c: At top level:
main.c:41:3: error: expected identifier or '(' before 'return'
   41 |   return (0);
      |   ^~~~~~
main.c:42:1: error: expected identifier or '(' before '}' token
   42 | }
      | ^
main.c:43:1: error: expected identifier or '(' before '}' token
   43 | }
      | ^
Language: C

#include<stdio.h>

int main(void) {
int H,W;
int x,y;
int flagx = 0;
int flagy = 0;

while(scanf("%d %d", &H, &W), (H+W) != 0) {
  for (y = 0; y < H; y++) {
    if (flagy == 0) {
      flagy = 1;
    } else {
      flagy = 0;
    }
    for (x = 0; x < W; x++) {
      if (x == 0) {
        if (flagy == 1) {
          printf("#");
          flagy = 0;
          flagx = 0;
        } else {
          printf(".");
          flagy = 1;
          flagx = 1;
        }
      } else {
        if (flagx == 1) {
          pritnf("#");
          flagx = 0;
        } else {
          printf(".");
          flagx = 1;
        }
      }
    }
  printf("\n");
  }
  printf("\n");
}
  return (0);
}

Compiler output:
main.c: In function 'main':
main.c:29:11: error: implicit declaration of function 'pritnf'; did you mean 'printf'? [-Wimplicit-function-declaration]
   29 |           pritnf("#");
      |           ^~~~~~
      |           printf
Language: C

#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		return 0;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
}

Compiler output:
main.c: In function 'main':
main.c:34:15: error: expected expression before '=' token
   34 |         if(H<==0 && W <== 0){
      |               ^
Language: C

#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		return 0;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		return 0;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:34:15: error: expected expression before '=' token
   34 |         if(H<==0 && W <== 0){
      |               ^
main.c: In function 'main':
main.c:75:15: error: expected expression before '=' token
   75 |         if(H<==0 && W <== 0){
      |               ^
main.c: In function 'main':
main.c:84:1: error: expected declaration or statement at end of input
   84 | }
      | ^
Language: C

#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		return 0;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		break;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:34:15: error: expected expression before '=' token
   34 |         if(H<==0 && W <== 0){
      |               ^
main.c: In function 'main':
main.c:75:15: error: expected expression before '=' token
   75 |         if(H<==0 && W <== 0){
      |               ^
main.c:76:17: error: break statement not within loop or switch
   76 |                 break;
      |                 ^~~~~
main.c: In function 'main':
main.c:84:1: error: expected declaration or statement at end of input
   84 | }
      | ^
Language: C

#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H <= 0 && W <= 0){
		return 0;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	#include <stdio.h>

void White (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('#');
		if(j % 2 == 1) putchar('.');
	}
}

void Black (int W){
	int j;
	for(j=0; j<W; j++){
		if(j % 2 == 0) putchar('.');
		if(j % 2 == 1) putchar('#');
	}
}

void printing (int i, int W){
	if(i % 2 == 0){
		White(W);
		putchar('\n');
	}
	if(i % 2 == 1){
		Black(W);
		putchar('\n');
	}
}

int main(void){
	int H,W,i,j;
	scanf("%d %d", &H, &W);
	
	if(H<==0 && W <== 0){
		break;
	}else{
		for(i=0; i<H; i++){
			//H????????§?????????????????????
			printing(i,W);
		}
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:75:15: error: expected expression before '=' token
   75 |         if(H<==0 && W <== 0){
      |               ^
main.c:76:17: error: break statement not within loop or switch
   76 |                 break;
      |                 ^~~~~
main.c: In function 'main':
main.c:84:1: error: expected declaration or statement at end of input
   84 | }
      | ^
Language: C

#include <stdio.h>

int main(void)
{
	int H, W, h, w;

	while (1)
	{
		scanf("%d %d", &H, &W);

		if ((H == 0) && (W == 0))
		{
			break;
		}
		for (h = 0; h<H; h++)
		{
			for (w = 0; w<W; w++)
			{
				if ((h + w) % 2 == 0)
				{
					printf("#");
				}
				else
				{
					printf(".");
				}
			}
		}   printf("\n");
	}   printf("\n");
}

    return 0;
}

Compiler output:
main.c:32:5: error: expected identifier or '(' before 'return'
   32 |     return 0;
      |     ^~~~~~
main.c:33:1: error: expected identifier or '(' before '}' token
   33 | }
      | ^
Language: C

#include<stdio.h>

int main()
{
int h,w,i,t,j=1;
while(1){
scanf("%d %d",&h,&w);
if(h==0&&w==0)break;
for(i=0;i<h;i++){
j=r;
for(t=0;t<w+1;t++){
if((j%2)==1)printf("#");
if((j%2)==0)printf(".");
j++;
}
printf("\n");
r++;
}
printf("\n");
}
return 0;
}

Compiler output:
main.c: In function 'main':
main.c:10:3: error: 'r' undeclared (first use in this function)
   10 | j=r;
      |   ^
main.c:10:3: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include<stdio.h>

int main(void){

	int H,W;

	scanf("%d %d",H,W);

	for(i=0;i<H;i++){
		if(i%2==0){
			for(j=0;j<W;j++){
				if(j%2==0){
					printf("#");
				}
				else{
					printf(".");
				}
			}
		else{
			for(j=0;j<W;j++){
				if(j%2==0){
					printf(".");
				}
				else{
					printf("#");
				}	
			}
		}
		printf("\n");
		if(i==H-1)printf("\n");
	}
	return 0;
}
		

Compiler output:
main.c: In function 'main':
main.c:9:13: error: 'i' undeclared (first use in this function)
    9 |         for(i=0;i<H;i++){
      |             ^
main.c:9:13: note: each undeclared identifier is reported only once for each function it appears in
main.c:11:29: error: 'j' undeclared (first use in this function)
   11 |                         for(j=0;j<W;j++){
      |                             ^
main.c:19:17: error: expected '}' before 'else'
   19 |                 else{
      |                 ^~~~
Language: C

#include<stdio.h>

int main(void){

	int H,W;
	int i,j;

	scanf("%d %d",H,W);

	for(i=0;i<H;i++){
		if(i%2==0){
			for(j=0;j<W;j++){
				if(j%2==0){
					printf("#");
				}
				else{
					printf(".");
				}
			}
		else{
			for(j=0;j<W;j++){
				if(j%2==0){
					printf(".");
				}
				else{
					printf("#");
				}	
			}
		}
		printf("\n");
		if(i==H-1)printf("\n");
	}
	return 0;
}
		

Compiler output:
main.c: In function 'main':
main.c:20:17: error: expected '}' before 'else'
   20 |                 else{
      |                 ^~~~
Language: C

#include <stdio.h>
int main(void){
    // Here your code !
    int H,W,i,k;
    
    while(1){
        scanf("%d%d",&H,&W);
        if(H == 0 || W == 0){
            return 0;
        }
        for(i = 2;i <= H+1;i++){
            for(k = 2;k <= W+1;k++){
                if(i%2 == 0){
                    if(k%2 == 0){
                        printf("#");
                    }
                    else{
                        printf(".");
                    }
                }
                else{
                    if(k%2 == 0){
                        printf(".");
                    }
                    else{
                        printf("#");
                    }
                }
            }
            printf("\n");
            
        }
        printf("\n");
        
    }

Compiler output:
main.c: In function 'main':
main.c:35:5: error: expected declaration or statement at end of input
   35 |     }
      |     ^
Language: C

#include <stdio.h>
int main(void){
    int H,W,i,k;
    
    while(1){
        scanf("%d%d",&H,&W);
        if(H == 0 || W == 0){
            return 0;
        }
        for(i = 2;i <= H+1;i++){
            for(k = 2;k <= W+1;k++){
                if(i%2 == 0){
                    if(k%2 == 0){
                        printf("#");
                    }
                    else{
                        printf(".");
                    }
                }
                else{
                    if(k%2 == 0){
                        printf(".");
                    }
                    else{
                        printf("#");
                    }
                }
            }
            printf("\n");
            
        }
        printf("\n");
        
    }

Compiler output:
main.c: In function 'main':
main.c:34:5: error: expected declaration or statement at end of input
   34 |     }
      |     ^
Language: C

#include<stdio.h>
 
void printRectangle(int H, int W){
    int i,j,k;
     
    for(i=0; i<H; i++){
        for(j=0; j<W; j++){
            k = i+j;
            if(k%2 == 0)  printf("#");
            else printf(".");
            check_cnt++;
        }
        printf("\n");
    }
    printf("\n");
}
 
int main(void){
     
    int h,w;
     
    while(1){
        scanf("%d %d", &h, &w);
        if(h==0 && w==0) break;
        printRectangle(h, w);
    }
    return 0;
}

Compiler output:
main.c: In function 'printRectangle':
main.c:11:13: error: 'check_cnt' undeclared (first use in this function)
   11 |             check_cnt++;
      |             ^~~~~~~~~
main.c:11:13: note: each undeclared identifier is reported only once for each function it appears in
Language: C

#include<stdio.h>
int main(void){
	int h = 1, w = 1, countah, countaw, counta=0;
	while (h != 0 && w != 0){


		scanf_s("%d", &h);
		scanf_s("%d", &w);


		for (countah = 1; countah <= h; countah++){

			for (countaw = 1; countaw <= w; countaw++){
				counta=counta++;
				if (counta % 2 != 0){
					printf("#");
				}

				else{
					printf(".");
				}


			}
			printf("\n");


		}

	}

	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:7:17: error: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
    7 |                 scanf_s("%d", &h);
      |                 ^~~~~~~
      |                 scanf
Language: C

#include<stdio.h>

int main(void){
    int i,j,h,w,start,next;

    while(1){
        scanf("%d %d",&h,&w);
        if(h == 0 && w == 0)
            break;
        start = 1;
        for(i = 0;i < h;i++){
            next = start;
            for(j = 0;j < w;j++){
                if(next == 1)
                    printf("#");
                else
                    printf(".");
                next *= -1;
            }
            printf("\n");
            start *= -1;
        }
        printf("\n);
    }
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:23:16: warning: missing terminating " character
   23 |         printf("\n);
      |                ^
main.c:23:16: error: missing terminating " character
   23 |         printf("\n);
      |                ^~~~~
main.c:24:5: error: expected expression before '}' token
   24 |     }
      |     ^
main.c:23:16: error: expected ';' before '}' token
   23 |         printf("\n);
      |                ^
      |                ;
   24 |     }
      |     ~
Language: C

#include<stdio.h>
int main(void){
	int i,j,H,W;
	while(1){
		scanf("%d %d",&H,&W);
		count = 0;
		j = 0;
		if(H==0 && W == 0) break;
		else if(H ==0 || W == 0) printf("\n");
		else {
			for(i=0;i<H;i++){
				count = i % 2;
				if(count == 0){
					while(1){
						printf("#");
						j++;
						if(j == W) break;
						printf(".");
						j++;
						if(j == W) break;
					}
				}
				else{
					while(1){
						printf(".");
						j++;
						if(j == W) break;
						printf("#");
						j++;
						if(j == W) break; 
					}
				}
				printf("\n");
		}
	printf("\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:6:17: error: 'count' undeclared (first use in this function)
    6 |                 count = 0;
      |                 ^~~~~
main.c:6:17: note: each undeclared identifier is reported only once for each function it appears in
main.c:38:1: error: expected declaration or statement at end of input
   38 | }
      | ^
Language: C

#include<stdio.h>
int main(void){
	int i,j,H,W,count;
	while(1){
		scanf("%d %d",&H,&W);
		count = 0;
		j = 0;
		if(H==0 && W == 0) break;
		else if(H ==0 || W == 0) printf("\n");
		else {
			for(i=0;i<H;i++){
				count = i % 2;
				if(count == 0){
					while(1){
						printf("#");
						j++;
						if(j == W) break;
						printf(".");
						j++;
						if(j == W) break;
					}
				}
				else{
					while(1){
						printf(".");
						j++;
						if(j == W) break;
						printf("#");
						j++;
						if(j == W) break; 
					}
				}
				printf("\n");
		}
	printf("\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:38:1: error: expected declaration or statement at end of input
   38 | }
      | ^
Language: C

#include<stdio.h>

int main(){
 int i,H,W,j;
 scanf("%d%d",&H,&W);
 while(H*H+W*W){
  for(j=0;j<H;j++){
   if(j%2){
    for(i=0;i<(W/2-1);i++){
     printf(".#");}
    if(W%2){
     printf(".");}
    else{
     printf(".#");}}
   else{
    for(i=0;i<(W/2-1);i++){
     printf("#.");}
    if(W%2){
     printf("#");}
    else{
     printf("#.");}}}
   printf("\n");}
  printf("\n");
  scanf("%d%d",&H,&W);}
 return 0;}

Compiler output:
main.c:25:2: error: expected identifier or '(' before 'return'
   25 |  return 0;}
      |  ^~~~~~
main.c:25:11: error: expected identifier or '(' before '}' token
   25 |  return 0;}
      |           ^
Language: C

#include<stdio.h>

int main(){
 int i,H,W,j;
 scanf("%d%d",&H,&W);
 while(H*H+W*W){
  for(j=0;j<H;j++){
   if(j%2){
    for(i=0;i<(W/2-1);i++){
     printf(".#");}
    if(W%2){
     printf(".");}
    else{
     printf(".#");}}
   else{
    for(i=0;i<(W/2-1);i++){
     printf("#.");}
    if(W%2){
     printf("#");}
    else{
     printf("#.");}}
   printf("\n");}
  printf("\n");}
  scanf("%d%d",&H,&W);}
 return 0;}

Compiler output:
main.c:25:2: error: expected identifier or '(' before 'return'
   25 |  return 0;}
      |  ^~~~~~
main.c:25:11: error: expected identifier or '(' before '}' token
   25 |  return 0;}
      |           ^
Language: C

#include<stdio.h>

int main(void){
	int H,W;
	int i,j;
	while(1){
		scanf("%d %d",&H,&W);
		if(H==0&&W==0)	break;
		for(i=0;i<H;i++){
			for(j=0;j<W;j++){
				if((j+i)%2==0)	printf("#");
				else printf(".");
			}
			printf("\n);
		}
		printf("\n");
	}
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:14:32: warning: missing terminating " character
   14 |                         printf("\n);
      |                                ^
main.c:14:32: error: missing terminating " character
   14 |                         printf("\n);
      |                                ^~~~~
main.c:15:17: error: expected expression before '}' token
   15 |                 }
      |                 ^
main.c:14:32: error: expected ';' before '}' token
   14 |                         printf("\n);
      |                                ^
      |                                ;
   15 |                 }
      |                 ~
Language: C

#include <stdio.h>
int main()
{
  int h,w;
  int i,j;
  scanf("%d",&h);
  scanf("%d",&w);
  while(!((h==0) && (w==0))){
    for(i=0;i<h;i++){
      for(j=0;j<w;j++){
        if ((i%2==0) && (j%2==0)){
          printf("#");
        }else if ((i%2==0) && (j%2==1)){
          printf(".");
        }else if ((i%2==1) && (j%2==0)){
          printf(".");
        }else if ((i%2==1) && (j%2==1)){
          printf("#");
        }
      }
      printf("\n");
    }
    printf("\n");
    scanf("%d",&h);
    scanf("%d",&w);
  }
 
 
  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;
      |   ^~~~~~