Compilare: user.cpp: In function ‘void solve1()’: user.cpp:32:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size() && v[i].e == 0; i++) ^ user.cpp: In function ‘void solve2()’: user.cpp:47:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) ^ user.cpp: In function ‘void solve3()’: user.cpp:66:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:87:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < s.size(); j++) ^