foo.c:13:6: warning: return type of 'main' is not 'int' [-Wmain]
   13 | void main()
      |      ^~~~
foo.c: In function 'main':
foo.c:16:21: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |  for ( i=0;i<N;i++ )scanf("%d",&a[i]);
      |                     ^~~~~~~~~~~~~~~~~
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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