Compilare: main.cpp: In function 'int main()': main.cpp:12:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("trenuri3.in","r",stdin); ^ main.cpp:13:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("trenuri3.out","w",stdout); ^ main.cpp:14:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &n, &m); ^ main.cpp:17:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &x, &y); ^ main.cpp:22:51: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &b[i].first, &b[i].second); ^