foo.c: In function 'main':
foo.c:20:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   20 |  scanf("%d%d",&n1,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~
foo.c:24:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   24 |  scanf("%d",&a[c]);}
      |  ^~~~~~~~~~~~~~~~~
foo.c:27:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%d",&b[c]);}
      |  ^~~~~~~~~~~~~~~~~

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