foo.cc: In function 'int main()':
foo.cc:31:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |    scanf("%d",&tree[i].m);
      |    ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:33:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |    scanf("%d",&tree[i].b);
      |    ~~~~~^~~~~~~~~~~~~~~~~

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