Compilare: user.cpp: In function ‘int main()’: user.cpp:75:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < moments[i].size(); j++) { ^ user.cpp:81:49: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j + 1 < moments[i].size(); j++) ^ user.cpp:80:13: warning: unused variable ‘x’ [-Wunused-variable] int x = moments[i].size(); ^ user.cpp:91:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1; j < moments[i].size(); j++) ^