foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d", &c);
      |  ^~~~~~~~~~~~~~~
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d", &d);
      |  ^~~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d", &e);
      |   ^~~~~~~~~~~~~~~
foo.c:13:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   13 |   scanf("%d", &e);
      |   ^~~~~~~~~~~~~~~

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