foo.c: In function 'insert':
foo.c:23:1: warning: control reaches end of non-void function [-Wreturn-type]
   23 | }
      | ^
foo.c: In function 'main':
foo.c:27:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:29:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:30:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   30 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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