Compilare: user.cpp: In function ‘int main()’: user.cpp:68:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size(); i++) { ^ user.cpp:18:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("kss.in", "r", stdin); ^ user.cpp:19:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("kss.out", "w", stdout); ^ user.cpp:21:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp:24:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %lld", &n, &k); ^ user.cpp:25:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", &s[1]); ^