/in/foo.cc: In function 'int main()':
/in/foo.cc:9:40: 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",&s[i]);
                                        ^
/in/foo.cc:15:6: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
    if(a[j])
      ^