/in/foo.cc: In function 'int main()':
/in/foo.cc:42:20: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
    scanf("%d",&a[i]);
                    ^
/in/foo.cc:74:17: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
  printf("%d",ans);
                 ^