Compilare: user.cpp: In function ‘void afisare()’: user.cpp:23:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<a[i].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:56:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<a[i].size();j++) ^ user.cpp: In function ‘void er(int, int)’: user.cpp:97:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<a[i].size();j++) ^ user.cpp:103:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<a[i].size();j++) ^