foo.cc: In function 'int main()':
foo.cc:42:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while (i < sh.size()) {
                ~~^~~~~~~~~~~
foo.cc:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while (i < sh.size() && t >= sh[i].first) { //在可选范围中选取右端点最大的
                    ~~^~~~~~~~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。