# Ullman (Compiler Design) Edition 2 Exercise 6.1 Question 1 (Page No. 362)

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Construct the DAG for the expression
$((x + y)-((x + y)\ast(x -y))) + ((x+y)\ast(x-y))$

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((x+y)−((x+y)∗(x−y))) and ((x+y)∗(x−y)) expression needed to be added together at the end. So according to me, DAG should be following... DAG for the expression ((x+y)−((x+y)∗(x−y)))+((x+y)∗(x−y)) 2
I think you missed this part "minus from the Top should be connected to multiply" because of this condition ((x+y)−((x+y)∗(x−y)))

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