foo.c: In function 'main':
foo.c:14:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:15:22: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=0;i<n;i++)scanf("%d",&a[i]);
                      ^~~~~~~~~~~~~~~~~
foo.c:16:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  int x;scanf("%d",&x);
        ^~~~~~~~~~~~~~

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