Compilare: user.cpp: In function ‘void solve(int)’: user.cpp:113:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1; i < to_move.size(); i++) move(to_move[i], to_move[i - 1]); ^ user.cpp: In function ‘int main()’: user.cpp:119:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tije.in","r",stdin); ^ user.cpp:121:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp: In constructor ‘Buffer::Buffer(std::string, int)’: user.cpp:25:47: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(name.c_str(), "w", stdout); ^