/in/foo.c: In function 'main':
/in/foo.c:4:2: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
  scanf("%d%d",&j,&k);
  ^~~~~
/in/foo.c:4:2: warning: incompatible implicit declaration of built-in function 'scanf'
/in/foo.c:4:2: note: include '<stdio.h>' or provide a declaration of 'scanf'
/in/foo.c:8:22: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(j%400==0||j%4==0&&j%100!=0)
                ~~~~~~^~~~~~~~~~
/in/foo.c:11:2: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
  printf("%d",cnt);
  ^~~~~~
/in/foo.c:11:2: warning: incompatible implicit declaration of built-in function 'printf'
/in/foo.c:11:2: note: include '<stdio.h>' or provide a declaration of 'printf'