foo.c: In function 'ss':
foo.c:4:8: warning: unused variable 'k' [-Wunused-variable]
    4 |  int i,k=0;
      |        ^
foo.c: In function 'PrimeCount':
foo.c:25:1: warning: control reaches end of non-void function [-Wreturn-type]
   25 | }
      | ^
foo.c: In function 'main':
foo.c:30:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   30 |  scanf("%d",&n1);
      |  ^~~~~~~~~~~~~~~
foo.c:31:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   31 |  scanf("%d",&n2);
      |  ^~~~~~~~~~~~~~~
foo.c:35:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   35 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:37:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   37 |   scanf("%d",&b[i]);
      |   ^~~~~~~~~~~~~~~~~

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