foo.c: In function 'input':
foo.c:6:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:32:15: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   32 |  int n1,n2,n3;scanf("%d%d%d",&n1,&n2,&n3);
      |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~

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