Compilare: user.cpp: In function ‘void dfs(int, int, int)’: user.cpp:23:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( St.size() != D[Y] ) { ^ user.cpp:40:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( St.size() != C[X] ) { ^ user.cpp: In function ‘int main(int, const char**)’: user.cpp:78:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < Ans[k].size(); i ++ ) ^