foo.c: In function 'main':
foo.c:17:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   17 |  for(;x;x/=10)
      |  ^~~
foo.c:20:6: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   20 |      if(x==0)
      |      ^~
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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