Compilare: user.cpp: In function ‘int main()’: user.cpp:19:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("proc.in", "r", stdin); ^ user.cpp:20:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("proc.out", "w", stdout); ^ user.cpp:21:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld %lld", &N, &k, &p); ^ user.cpp:23:27: warning: ‘dr’ is used uninitialized in this function [-Wuninitialized] long long st, dr, ans = dr; ^