foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d %d", &l, &m);
      |  ^~~~~~~~~~~~~~~~~~~~~~
foo.c:11:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |    scanf("%d", &x[i][j]);
      |    ^~~~~~~~~~~~~~~~~~~~~

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