/in/foo.cc: In function 'int main()':
/in/foo.cc:9:10: warning: variable 'sum' set but not used [-Wunused-but-set-variable]
  int n,q,sum,pos1,pos2;
          ^~~
/in/foo.cc:32:14: warning: 'pos2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   cout<<pos2-pos1<<endl;
              ^~~~
/in/foo.cc:32:14: warning: 'pos1' may be used uninitialized in this function [-Wmaybe-uninitialized]