foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&n1);
      |  ^~~~~~~~~~~~~~~
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d",&n2);
      |  ^~~~~~~~~~~~~~~
foo.c:10:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:14:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |   scanf("%d",&b[j]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'PrimeCount':
foo.c:47:1: warning: control reaches end of non-void function [-Wreturn-type]
   47 | }
      | ^

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