foo.c: In function 'main':
foo.c:31:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d", &m,&n,&p);
     ^~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:33:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &a[i]);
         ^~~~~~~~~~~~~~~~~~
foo.c:35:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &b[i]);
         ^~~~~~~~~~~~~~~~~~
foo.c:37:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &c[i]);
         ^~~~~~~~~~~~~~~~~~

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