Compilare: user.cpp: In function ‘int main()’: user.cpp:65:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); ++ i) ^ user.cpp:66:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] cout << sol[i] << " \n"[i + 1 == sol.size()]; ^ user.cpp:40:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("color2.in", "r", stdin); ^ user.cpp:41:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("color2.out", "w", stdout); ^