/in/foo.cc: In function 'int main()':
/in/foo.cc:8:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<strlen(s);i++)
               ^
/in/foo.cc:10:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(k>=strlen(s)/2)cout<<"Yes\n";
      ^