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("%d %d",&m,&n);
      |  ^~~~~~~~~~~~~~~~~~~~
foo.c:12:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |   scanf("%d",&a[i][j]);
      |   ^~~~~~~~~~~~~~~~~~~~

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