Compilare: user.cpp: In constructor ‘Rmq::Rmq(const std::vector<int>&)’: user.cpp:14:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < nums.size(); ++i) { ^ user.cpp: In member function ‘void Rmq::Calculate()’: user.cpp:20:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 1; k < m_[0].size(); ++k) { ^ user.cpp:21:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i + (1 << k) < m_.size(); ++i) { ^ user.cpp: In member function ‘void Rmq::Debug()’: user.cpp:35:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < m_.size(); ++i, printf("\n")) { ^ user.cpp:36:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < m_[i].size(); ++j) { ^ user.cpp: In function ‘int main()’: user.cpp:46:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rmq.in","r",stdin); ^ user.cpp:47:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rmq.out","w",stdout); ^ user.cpp:50:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:53:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &nums[i]); ^ user.cpp:58:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^