Compilare: user.cpp: In function ‘void solve(int, int, std::vector<int>&)’: user.cpp:65:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < Q1.size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:112:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("armate.in","r",stdin); ^ user.cpp:113:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("armate.out","w",stdout); ^