/in/foo.cc: In function 'll BFS()':
/in/foo.cc:43:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (ll i = 0; i < tab[h].size(); i++)
                        ~~^~~~~~~~~~~~~~~
/in/foo.cc: In function 'll dinic(ll, ll)':
/in/foo.cc:60:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (ll i = current[x]; i < tab[x].size(); i++)
                             ~~^~~~~~~~~~~~~~~
/in/foo.cc: In function 'll DINIC()':
/in/foo.cc:85:42: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
         while (flow = dinic(S, 0x3f3f3f3f))  // 一次BFS可以进行多次增广
                                          ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:104:8: warning: unused variable 'total' [-Wunused-variable]
     ll total = 0;
        ^~~~~