foo.cc: In function 'int main()':
foo.cc:21:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |  scanf("%d %d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:26:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |    scanf("%c",&a[i][j]);
      |    ~~~~~^~~~~~~~~~~~~~~

Found 10 testcases.
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