/in/foo.cc: In function 'void dfs(int, int)':
/in/foo.cc:15:61: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while ((a[x+lg*d[ii]][y+lg*e[ii]]==c[k][lg])&&(c[k].size()>1+lg))
                                                  ~~~~~~~~~~~^~~~~
/in/foo.cc:19:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (lg>c[k].size()) 
       ~~^~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:29:13: warning: right operand of comma operator has no effect [-Wunused-value]
  cin>>m>>n,c;
             ^