Compilare: user.c: In function ‘main’: user.c:13:21: warning: unused variable ‘i’ [-Wunused-variable] long long n, m, i, size, nr = 0, x, y, z; ^ user.c:11:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("invazia.in","r", stdin); ^ user.c:12:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("invazia.out","w",stdout); ^ user.c:18:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lli%lli\n",&n, &m); ^ user.c:20:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &c); ^ user.c:22:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lli%lli%lli\n", &x, &y, &z); ^ user.c:38:22: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^ user.c:42:22: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lli\n",&x); ^