<p>A binary tree is named <strong>Even-Odd</strong> if it meets the following conditions:</p> <ul> <li>The root of the binary tree is at level index <code>0</code>, its children are at level index <code>1</code>, their children are at level index <code>2</code>, etc.</li> <li>For every <strong>even-indexed</strong> level, all nodes at the level have <strong>odd</strong> integer values in <strong>strictly increasing</strong> order (from left to right).</li> <li>For every <b>odd-indexed</b> level, all nodes at the level have <b>even</b> integer values in <strong>strictly decreasing</strong> order (from left to right).</li> </ul> <p>Given the <code>root</code> of a binary tree, <em>return </em><code>true</code><em> if the binary tree is <strong>Even-Odd</strong>, otherwise return </em><code>false</code><em>.</em></p> <p> </p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://assets.leetcode.com/uploads/2020/09/15/sample_1_1966.png" style="width: 362px; height: 229px;" /> <pre> <strong>Input:</strong> root = [1,10,4,3,null,7,9,12,8,6,null,null,2] <strong>Output:</strong> true <strong>Explanation:</strong> The node values on each level are: Level 0: [1] Level 1: [10,4] Level 2: [3,7,9] Level 3: [12,8,6,2] Since levels 0 and 2 are all odd and increasing and levels 1 and 3 are all even and decreasing, the tree is Even-Odd. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://assets.leetcode.com/uploads/2020/09/15/sample_2_1966.png" style="width: 363px; height: 167px;" /> <pre> <strong>Input:</strong> root = [5,4,2,3,3,7] <strong>Output:</strong> false <strong>Explanation:</strong> The node values on each level are: Level 0: [5] Level 1: [4,2] Level 2: [3,3,7] Node values in level 2 must be in strictly increasing order, so the tree is not Even-Odd. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://assets.leetcode.com/uploads/2020/09/22/sample_1_333_1966.png" style="width: 363px; height: 167px;" /> <pre> <strong>Input:</strong> root = [5,9,1,3,5,7] <strong>Output:</strong> false <strong>Explanation:</strong> Node values in the level 1 should be even integers. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the tree is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 <= Node.val <= 10<sup>6</sup></code></li> </ul>