Compilare: user.cpp: In function ‘int main()’: user.cpp:48:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (maxlen < v.length()) maxlen = v.length(); ^ user.cpp:49:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < v.length(); j++) ^ user.cpp:57:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (v == "" && s[i].length() == maxlen) v = s[i]; ^ user.cpp:58:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (s[i].length() == maxlen && v > s[i]) v = s[i]; ^ user.cpp:88:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size(); i++) ^