foo.c: In function 'main':
foo.c:9:17: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
    9 |         scanf("%d",a[i]);
      |                ~^  ~~~~
      |                 |   |
      |                 |   int
      |                 int *
foo.c:9:9: warning: '*a[<unknown>]' is used uninitialized [-Wuninitialized]
    9 |         scanf("%d",a[i]);
      |         ^~~~~~~~~~~~~~~~
foo.c:12:23: warning: '*a[<unknown>]' may be used uninitialized [-Wmaybe-uninitialized]
   12 |                 a[i]=a[n-i+1];
      |                      ~^~~~~~~

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