/in/foo.cc: In function 'int main()':
/in/foo.cc:11:18: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'int' [-Wformat=]
  scanf("%d%d",m,n);
                  ^
/in/foo.cc:11:18: warning: format '%d' expects argument of type 'int*', but argument 3 has type 'int' [-Wformat=]
/in/foo.cc:23:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<toNode[i].size();j++){
               ~^~~~~~~~~~~~~~~~~