Compilare: user.cpp: In function ‘void parse(int, int)’: user.cpp:23:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; i < mat[l][c].size(); i++) ^ user.cpp:44:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < aux.size(); i++) { ^ user.cpp:45:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i != aux.size() - 1 && aux[i].second != 0 && aux[i + 1].first == ':') { ^