foo.c: In function 'main':
foo.c:6:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&n);
 ^~~~~~~~~~~~~~
foo.c:7:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&num);
 ^~~~~~~~~~~~~~~~
foo.c:11:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
          scanf("%d",&num);
          ^~~~~~~~~~~~~~~~

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