# LeetCode: Flatten Binary Tree To Linked List Solution

1/**2 * Definition for a binary tree node.3 * function TreeNode(val, left, right) {4 * this.val = (val===undefined ? 0 : val)5 * this.left = (left===undefined ? null : left)6 * this.right = (right===undefined ? null : right)7 * }8 */9/**10 * @param {TreeNode} root11 * @return {void} Do not return anything, modify root in-place instead.12 */13var flatten = function (root) {14 let iter = root15 while (iter) {16 if (iter.left) {17 let last = iter.left18 while (last.right) last = last.right19 last.right = iter.right20 iter.right = iter.left21 iter.left = null22 }23 iter = iter.right24 }25}

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leetcode

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