foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&x);
  ^~~~~~~~~~~~~~
foo.c:15:2: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("\n%d",n+1);
  ^~~~~~~~~~~~~~~~~~

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