/
EvenOddTree.java
61 lines (57 loc) · 1.67 KB
/
EvenOddTree.java
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/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
// https://leetcode.com/problems/even-odd-tree
class Solution {
public boolean isEvenOddTree(TreeNode root) {
Deque<TreeNode> queue = new ArrayDeque<>();
queue.add(root);
int level = 1;
while (!queue.isEmpty()) {
Deque<TreeNode> temp = new ArrayDeque<>();
int last = -1;
while (!queue.isEmpty()) {
TreeNode node = queue.removeFirst();
int x = node.val;
if (last == -1) {
if (x % 2 == level % 2) {
last = x;
} else {
return false;
}
} else {
if (x % 2 == level % 2) {
if (level % 2 == 1 && x <= last) {
return false;
}
if (level % 2 == 0 && x >= last) {
return false;
}
last = x;
} else {
return false;
}
}
if (node.left != null)
temp.addLast(node.left);
if (node.right != null)
temp.addLast(node.right);
}
queue = temp;
level += 1;
}
return true;
}
}