foo.c: In function 'main':
foo.c:8:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |    scanf("%d%d",&n,&m);
      |    ^~~~~~~~~~~~~~~~~~~
foo.c:11:13: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |             scanf("%d",&a[i][j]) ;
      |             ^~~~~~~~~~~~~~~~~~~~

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