foo.c: In function 'main':
foo.c:9:16: warning: statement with no effect [-Wunused-value]
   for(x=i;x>9;x/10)
               ~^~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~

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