Compilare: user.cpp: In function ‘bool str(my, my)’: user.cpp:13:69: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] return ((a.s.size() < b.s.size()) || (a.s.size() == b.s.size()) && a.s < b.s); ^ user.cpp: In function ‘bool cmp(std::string, std::string)’: user.cpp:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) ^ user.cpp:22:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) ^ user.cpp:27:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i == a.size()) return 1; ^ user.cpp: In function ‘int main()’: user.cpp:40:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (a[i].size() == maxx) return cout << a[i], 0; ^