foo.c: In function 'insert':
foo.c:18:9: warning: unused variable 'j' [-Wunused-variable]
   18 |  int i, j;
      |         ^
foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%d", &x);
      |  ^~~~~~~~~~~~~~~

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