foo.c: In function 'main':
foo.c:21:6: warning: unused variable 'na' [-Wunused-variable]
   21 |  int na = Insert(a, n, k);
      |      ^~
foo.c:14:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
foo.c:17:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:20:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   20 |  scanf("%d", &k);
      |  ^~~~~~~~~~~~~~~

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