Compilare: main.c: In function 'main': main.c:7:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("lgput.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:8:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen ("lgput.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:10:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &a); scanf("%lld", &b); ^~~~~~~~~~~~~~~~~ main.c:10:25: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &a); scanf("%lld", &b); ^~~~~~~~~~~~~~~~~