/in/foo.c: In function 'main':
/in/foo.c:11:11: warning: format '%ld' expects argument of type 'long int *', but argument 2 has type 'int *' [-Wformat=]
  scanf("%ld",&a[i]);
           ^
/in/foo.c:17:12: warning: format '%ld' expects argument of type 'long int', but argument 2 has type 'int' [-Wformat=]
  printf("%ld",ans);
            ^