foo.cc: In function 'int main()':
foo.cc:10:6: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
  if(b<c<d){printf("Yes");}
     ~^~
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&a);
  ~~~~~^~~~~~~~~

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