foo.c: In function 'main':
foo.c:4:63: warning: unused variable 'minj' [-Wunused-variable]
  int a[500][500], m, n, max, min, num = 0, maxj = 0,maxi = 0, minj = 0,cnt = 0;
                                                               ^~~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &m, &n);
  ^~~~~~~~~~~~~~~~~~~~~
foo.c:10:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &a[i][j]);
    ^~~~~~~~~~~~~~~~~~~~~

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