foo.c:28:6: warning: return type of 'main' is not 'int' [-Wmain]
   28 | void main()
      |      ^~~~
foo.c: In function 'main':
foo.c:31:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   31 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:34:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   34 |   scanf("%d",&a[b]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:36:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   36 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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