Package g1101_1200.s1130_minimum_cost_tree_from_leaf_values

Class Solution

java.lang.Object
g1101_1200.s1130_minimum_cost_tree_from_leaf_values.Solution
public class Solution extends Object
1130 - Minimum Cost Tree From Leaf Values.<p>Medium</p> <p>Given an array <code>arr</code> of positive integers, consider all binary trees such that:</p> <ul> <li>Each node has either <code>0</code> or <code>2</code> children;</li> <li>The values of <code>arr</code> correspond to the values of each <strong>leaf</strong> in an in-order traversal of the tree.</li> <li>The value of each non-leaf node is equal to the product of the largest leaf value in its left and right subtree, respectively.</li> </ul> <p>Among all possible binary trees considered, return <em>the smallest possible sum of the values of each non-leaf node</em>. It is guaranteed this sum fits into a <strong>32-bit</strong> integer.</p> <p>A node is a <strong>leaf</strong> if and only if it has zero children.</p> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/08/10/tree1.jpg" alt="" /></p> <p><strong>Input:</strong> arr = [6,2,4]</p> <p><strong>Output:</strong> 32</p> <p><strong>Explanation:</strong> There are two possible trees shown. The first has a non-leaf node sum 36, and the second has non-leaf node sum 32.</p> <p><strong>Example 2:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/08/10/tree2.jpg" alt="" /></p> <p><strong>Input:</strong> arr = [4,11]</p> <p><strong>Output:</strong> 44</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 <= arr.length <= 40</code></li> <li><code>1 <= arr[i] <= 15</code></li> <li>It is guaranteed that the answer fits into a <strong>32-bit</strong> signed integer (i.e., it is less than 2<sup>31</sup>).</li> </ul>

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • mctFromLeafValues

      public int mctFromLeafValues(int[] arr)