foo.c: In function 'hs':
foo.c:15:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
  if (mbh <= m && mbh >= 1 && mbl <= n && mbl >= 1)
     ^
foo.c:21:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.c: In function 'main':
foo.c:25:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &m, &n);
  ^~~~~~~~~~~~~~~~~~~~~
foo.c:28:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &sz[i][j]);
    ^~~~~~~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务