foo.cc: In function 'void Dij()':
foo.cc:78:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0;i < a.size();++i) {
                   ~~^~~~~~~~~~

正在同步测试数据，请稍后
自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。