Compilare: main.cpp: In function 'int main()': main.cpp:31:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rege.in", "r", stdin); ^ main.cpp:32:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rege.out", "w", stdout); ^ main.cpp:35:59: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n%d %d\n%d %d", &n, &m, &l1, &c1, &l2, &c2); ^