/in/foo.cc:11:10: error: '::main' must return 'int'
 int main()
          ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:13:19: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
     scanf("%d", &n);
                   ^
/in/foo.cc:14:49: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
     for(int i = 1; i <= n; i++)scanf("%d", q + i);
                                                 ^
/in/foo.cc:28:23: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
     printf("%d\n", ans);
                       ^