Compilare: main.cpp: In function 'int main()': main.cpp:10:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("autostrazi2.in", "r", stdin); ^ main.cpp:11:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("autostrazi2.out", "w", stdout); ^ main.cpp:12:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] int n, m; scanf("%d %d", &n, &m); ^ main.cpp:14:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] int x, y; scanf("%d %d", &x, &y); ^