Compilare: user.cpp: In function ‘int main()’: user.cpp:70:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ksecv4.in", "r", stdin); ^ user.cpp:71:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ksecv4.out", "w", stdout); ^ user.cpp:73:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d %d", &N, &K, &M); ^ user.cpp:75:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lld", &A[i]); ^ user.cpp:77:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lld", &B[i]); ^ user.cpp: In function ‘bool ok(long long int)’: user.cpp:48:5: warning: ‘ras’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (int i=1; i<=N; i++) ^ user.cpp: In function ‘int main()’: user.cpp:94:24: warning: ‘ras’ may be used uninitialized in this function [-Wmaybe-uninitialized] printf ("%lld\n", (ras + 1) / 2); ^