/in/foo.cc: In function 'int main()':
/in/foo.cc:12:15: warning: 's' may be used uninitialized [-Wmaybe-uninitialized]
   12 |         cout<<s;
      |               ^
/in/foo.cc:5:15: note: 's' was declared here
    5 |         int n,s;
      |               ^