Compilare: user.cpp: In function ‘int main()’: user.cpp:113:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<ans.size(); i++) ^ user.cpp:80:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ghizi.in", "r", stdin); ^ user.cpp:81:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ghizi.out", "w", stdout); ^ user.cpp:83:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &N, &K); ^ user.cpp:87:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &t1, &t2); ^