foo.c: In function 'main':
foo.c:13:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   13 |     scanf("%d %d",&n,&a[1]);
      |     ^~~~~~~~~~~~~~~~~~~~~~~
foo.c:16:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:12:5: warning: 'n' is used uninitialized in this function [-Wuninitialized]
   12 |     int a[n];
      |     ^~~

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