foo.c: In function 'yz':
foo.c:10:1: warning: control reaches end of non-void function [-Wreturn-type]
   10 | }
      | ^
foo.c: In function 'main':
foo.c:14:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |  int x;scanf("%d",&x);
      |        ^~~~~~~~~~~~~~

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