foo.c: In function 'main':
foo.c:6:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&n);
   ^~~~~~~~~~~~~~
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&x);
   ^~~~~~~~~~~~~~
foo.c:10:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&a);
     ^~~~~~~~~~~~~~

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