Compilare: user.c: In function ‘check’: user.c:15:9: warning: unused variable ‘j’ [-Wunused-variable] int i, j, t = 1, p = 0, val = 0; ^ user.c: In function ‘read_and_solve’: user.c:32:7: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &N), NR = 0; ^ user.c:35:31: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] for(i = 1; i <= N; i++) scanf("%d ", &A[i]), d += (long)A[i], ^ user.c: In function ‘main’: user.c:53:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("auto.in", "rt", stdin); ^ user.c:54:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("auto.out", "wt", stdout); ^ user.c:58:7: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &teste); ^