foo.c: In function 'main':
foo.c:11:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d%d%d",&num1,&num2,&num3);
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:13:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&a[i]);
 ^~~~~~~~~~~~~~~~~
foo.c:15:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&b[i]);
 ^~~~~~~~~~~~~~~~~
foo.c:17:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&c[i]);
 ^~~~~~~~~~~~~~~~~