foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%c", &a[0]);
      |  ^~~~~~~~~~~~~~~~~~
foo.c:11:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |   scanf("%c", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:13:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   13 |  scanf("%c", &b[0]);
      |  ^~~~~~~~~~~~~~~~~~
foo.c:17:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |   scanf("%c", &b[j]);
      |   ^~~~~~~~~~~~~~~~~~

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