foo.c: In function 'main':
foo.c:43:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   43 |     scanf("%d", &num);
      |     ^~~~~~~~~~~~~~~~~
foo.c:46:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   46 |         scanf("%d%d%d%d", &a0, &a1, &b0, &b1);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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