foo.cc: In function 'int main()':
foo.cc:41:30: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::set<int>::size_type {aka long unsigned int}' [-Wformat=]
    printf("%d\n",wh[x].size());
                              ^

自豪的采用jd5进行评测(github.com/masnn/jd5)