/in/foo.cc: In function 'void dfsf(int)':
/in/foo.cc:14:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < fg[x].size(); i++)
                 ~~^~~~~~~~~~~~~~
/in/foo.cc: In function 'void dfs(int)':
/in/foo.cc:24:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < g[x].size(); i++)
                  ~~^~~~~~~~~~~~~
/in/foo.cc:32:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < g[x].size(); i++)
                  ~~^~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < g[q].size(); i++) 
                  ~~^~~~~~~~~~~~~
/in/foo.cc:58:7: warning: variable 'flag' set but not used [-Wunused-but-set-variable]
  bool flag; 
       ^~~~