Compilare: user.cpp: In function ‘std::pair<std::pair<long long int, int>, std::vector<int> > brute(int, std::vector<int>)’: user.cpp:109:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < which.size(); ++ i) ^ user.cpp: In function ‘std::pair<std::pair<long long int, int>, std::vector<int> > build_optimum(int, std::vector<int>)’: user.cpp:165:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < which.size(); ++ i) ^ user.cpp: In function ‘std::pair<std::pair<long long int, int>, std::vector<int> > solve(int, std::vector<int>)’: user.cpp:204:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < which.size(); ++ i) ^ user.cpp: In function ‘void generate_tests()’: user.cpp:277:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < test.size(); ++ j) ^ user.cpp:278:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] in << test[j] << " \n"[j + 1 == test.size()]; ^ user.cpp:284:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < ans.second.size(); ++ j) ^ user.cpp:285:68: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] out << ans.second[j] << " \n"[j + 1 == ans.second.size()]; ^ user.cpp: In function ‘void submit_solution()’: user.cpp:316:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < output.second.size(); ++ i) ^ user.cpp:317:71: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] cout << output.second[i] << " \n"[i + 1 == output.second.size()]; ^ user.cpp: In function ‘void generate_tests()’: user.cpp:240:43: warning: ignoring return value of ‘int system(const char*)’, declared with attribute warn_unused_result [-Wunused-result] system("ping localhost -n 2 >nul"); ^