foo.c: In function 'insert':
foo.c:17:2: warning: control reaches end of non-void function [-Wreturn-type]
   17 |  }
      |  ^
foo.c: In function 'main':
foo.c:21:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   21 |   scanf("%d",&n);
      |   ^~~~~~~~~~~~~~
foo.c:23:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   23 |    scanf("%d",&a[i]);
      |    ^~~~~~~~~~~~~~~~~
foo.c:24:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   24 |   scanf("%d",&x);
      |   ^~~~~~~~~~~~~~

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