foo.c: In function 'main':
foo.c:14:12: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   14 |  int m,n,p;scanf("%d%d%d",&m,&n,&p);
      |            ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:18:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   18 |    scanf("%d",&a[i][j]);
      |    ^~~~~~~~~~~~~~~~~~~~
foo.c:21:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   21 |    scanf("%d",&b[i][j]);
      |    ^~~~~~~~~~~~~~~~~~~~

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