/in/foo.c:1:8: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
 include<stdio.h>
        ^
/in/foo.c: In function 'main':
/in/foo.c:17:2: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
  scanf("%d",&n);
  ^~~~~
/in/foo.c:17:2: warning: incompatible implicit declaration of built-in function 'scanf'
/in/foo.c:17:2: note: include '<stdio.h>' or provide a declaration of 'scanf'
/in/foo.c:20:4: warning: implicit declaration of function 'gy' [-Wimplicit-function-declaration]
  j=gy(a[0],a[1]);
    ^~
/in/foo.c:23:2: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
  printf("%d",j);
  ^~~~~~
/in/foo.c:23:2: warning: incompatible implicit declaration of built-in function 'printf'
/in/foo.c:23:2: note: include '<stdio.h>' or provide a declaration of 'printf'