foo.c: In function 'main':
foo.c:22:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
foo.c:25:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:27:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%d", &x);
      |  ^~~~~~~~~~~~~~~
foo.c: In function 'insert':
foo.c:3:6: warning: 'w' may be used uninitialized in this function [-Wmaybe-uninitialized]
    3 |  int w;
      |      ^

[Hydro](https://hydro.ac)提供评测服务