Compilare: user.cpp: In function ‘void Push(int, int)’: user.cpp:21:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < V[i][j].size(); k++) ^ user.cpp: In function ‘void precalcV()’: user.cpp:52:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < X.size(); k++) ^ user.cpp:67:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < Y.size(); k++) ^ user.cpp:66:29: warning: variable ‘range’ set but not used [-Wunused-but-set-variable] pair <int, int> range = make_pair(0, 0); ^