/in/foo.cc: In function 'int main()':
/in/foo.cc:32:10: warning: unused variable 'k' [-Wunused-variable]
  int i,j,k=0;
          ^
/in/foo.cc:36:20: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<ha(s,i,j,n,m);
                    ^