foo.c: In function 'main':
foo.c:26:8: warning: unused variable 'n' [-Wunused-variable]
   26 |  int i,n,n2,a1[10000],a2[10000],n1;
      |        ^
foo.c: In function 'Unique':
foo.c:23:1: warning: control reaches end of non-void function [-Wreturn-type]
   23 | }
      | ^
foo.c: In function 'main':
foo.c:27:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%d%d",&n1,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~
foo.c:29:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |   scanf("%d",&a1[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:31:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   31 |   scanf("%d",&a2[i]);
      |   ^~~~~~~~~~~~~~~~~~

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