foo.c: In function 'number':
foo.c:11:1: warning: control reaches end of non-void function [-Wreturn-type]
   11 | }
      | ^
foo.c: In function 'main':
foo.c:16:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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