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:34:12: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   34 |  int n1,n2;scanf("%d%d",&n1,&n2);
      |            ^~~~~~~~~~~~~~~~~~~~~

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