package com.leetcode.tree;

/**

* Created by charles on 12/22/16.

*/

public class TreeNode {

public int val;

public TreeNode left;

public TreeNode right;

public TreeNode(int x) {

this.val = x;

left = null;

right = null;

}

@Override

public boolean equals(Object o) {

if (o == this) {

return true;

}

if (!(o instanceof TreeNode)) {

return false;

}

TreeNode node = (TreeNode) o;

/**

* be careful, for tree node, no need to check equal for left/right

*/

return node.val == ((TreeNode) o).val;

}

@Override

/** may need override hashcode if use treenode class with hashmap or set */

public int hashCode() {

int result = 17;

result = 31 * result + this.val;

return result;

}

}