LeetCode -- Same Tree

LeetCode -- Same Tree

題目描述：
Given two binary trees, write a function to check if they are equal or not.


Two binary trees are considered equal if they are structurally identical and the nodes have the same value.


比較兩個二叉樹是否完全相同。


思路：
直接對兩個樹從根節點同時DFS，使用全局成員來記錄是否相等即可。




實現代碼：

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     public int val;
 *     public TreeNode left;
 *     public TreeNode right;
 *     public TreeNode(int x) { val = x; }
 * }
 */
public class Solution {
    public bool IsSameTree(TreeNode p, TreeNode q) 
    {
        CompareTree(p, q);
    	return _same;
    }
private bool _same = true;
private void CompareTree(TreeNode p , TreeNode q)
{
	if(!_same){
		return;
	}
	
	if(p == null && q == null){
		return ;
	}
	if(p == null && q != null || q == null && p != null || p.val != q.val){
		_same = false;
		return;
	}
	CompareTree(p.left, q.left);
	CompareTree(p.right, q.right);
}


}