foo.c: In function 'main':
foo.c:8:17: warning: unused variable 'j' [-Wunused-variable]
 int num1,num2,i,j;
                 ^
foo.c:9:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d%d",&num1,&num2);
 ^~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:11:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&a[i]);
 ^~~~~~~~~~~~~~~~~
foo.c:13:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&b[i]);
 ^~~~~~~~~~~~~~~~~