/in/foo.cc: In function 'bool DFS(int, int)':
/in/foo.cc:23:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'void Dijkstra(int, int*)':
/in/foo.cc:38:9: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
   vv2[k]=0;
   ~~~~~~^~