foo.cc: In function 'int main()':
foo.cc:30:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |    scanf("%d",&tree[i].m);
      |    ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:32:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |    scanf("%d",&tree[i].b);
      |    ~~~~~^~~~~~~~~~~~~~~~~

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