foo.c: In function 'main':
foo.c:5:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |   scanf("%d",&n);
      |   ^~~~~~~~~~~~~~
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c: In function 'insert':
foo.c:14:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |   scanf("%d",&x);
      |   ^~~~~~~~~~~~~~
foo.c:16:7: warning: 'n' is used uninitialized in this function [-Wuninitialized]
   16 |  for(i=n;i>=0;i--)
      |      ~^~

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