foo.c: In function 'main':
foo.c:13:6: warning: unused variable 'i' [-Wunused-variable]
   13 |  int i = 0, t = 0;
      |      ^
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d%d", &m, &n);
      |  ^~~~~~~~~~~~~~~~~~~~~
foo.c:10:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |    scanf("%d", &a[i][j]);
      |    ^~~~~~~~~~~~~~~~~~~~~

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