/in/foo.cc: In function 'void Dijkstra1(int)':
/in/foo.cc:27:16: warning: 'gx' may be used uninitialized in this function [-Wmaybe-uninitialized]
         vis[gx]=1;
         ~~~~~~~^~
/in/foo.cc: In function 'void Dijkstra2(int)':
/in/foo.cc:54:16: warning: 'gx' may be used uninitialized in this function [-Wmaybe-uninitialized]
         vis[gx]=1;
         ~~~~~~~^~