Day 343

[vaskoz]

Good morning! Here's your coding interview problem for today.

This problem was asked by Google.

Given a binary search tree and a range [a, b] (inclusive), return the sum of the elements of the binary search tree within the range.

For example, given the following tree:

    5
   / \
  3   8
 / \ / \
2  4 6  10

and the range [4, 9], return 23 (5 + 4 + 6 + 8).