/in/foo.cc: In function 'int main()':
/in/foo.cc:20:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(mp.size()==m){
         ~~~~~~~~~^~~
/in/foo.cc:16:6: warning: unused variable 'i' [-Wunused-variable]
  int i=1,j=1,Ans=N;
      ^
/in/foo.cc:16:10: warning: unused variable 'j' [-Wunused-variable]
  int i=1,j=1,Ans=N;
          ^