Compilare: user.cpp: In function ‘int main()’: user.cpp:18:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zona.in", "r", stdin); ^ user.cpp:19:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zona.out", "w", stdout); ^ user.cpp:20:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &X, &Y, &N, &L); ^ user.cpp:26:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &d); ^ user.cpp:38:14: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] Sol1 = L - k; ^