/in/foo.cc: In function 'int main()':
/in/foo.cc:14:15: warning: 's' may be used uninitialized [-Wmaybe-uninitialized]
   14 |         cout<<s<<endl;
      |               ^
/in/foo.cc:6:15: note: 's' was declared here
    6 |         int n,s;
      |               ^