foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d %d",&n,&k);
      |  ^~~~~~~~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~

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