foo.c: In function 'input':
foo.c:4:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    4 |  int n;scanf("%d",&n);
      |        ^~~~~~~~~~~~~~
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:27:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |   int x;scanf("%d",&x);
      |         ^~~~~~~~~~~~~~

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