Consider the following tree
If the post order traversal gives ab-cd*+ then the label of the nodes 1,2,3,… will be
Explanation: Postorder traversal of the given binary tree will give the following sequence: 4 5 2 6 7 3 1.
Now comparing the sequence with a b – c d * + we get 1 = +, 2 = -, 3 = *, 4 = a, 5 = b, 6 = c and 7 = d.
So, option (A) is correct.
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