foo.cc: In function 'int main()':
foo.cc:23:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
foo.cc:26:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |            scanf("%d",&h[i][j]);
      |            ~~~~~^~~~~~~~~~~~~~~

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