foo.c: In function 'main':
foo.c:8:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |     scanf("%d%d",&m,&n);
      |     ^~~~~~~~~~~~~~~~~~~
foo.c:13:13: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   13 |             scanf("%d",&a[i][j]);
      |             ^~~~~~~~~~~~~~~~~~~~

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