foo.c: In function 'Setlnter':
foo.c:12:1: warning: control reaches end of non-void function [-Wreturn-type]
   12 | }
      | ^
foo.c: In function 'main':
foo.c:18:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   18 |  scanf("%d%d%d",&n1,&n2,&n3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:21:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   21 |   scanf("%d",&a1[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:23:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   23 |   scanf("%d",&a2[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:25:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |   scanf("%d",&a3[i]);
      |   ^~~~~~~~~~~~~~~~~~

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