foo.cc: In function 'int main()':
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d%d", &n,&m );
      |  ~~~~~^~~~~~~~~~~~~~~~
foo.cc:11:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |    scanf("%d", &arr[i][j]);
      |    ~~~~~^~~~~~~~~~~~~~~~~~

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