Leetcode100 Same Tree

这题比较简单，思路和之前做过的Merge Two Trees类似，都是对树的遍历进行简单运用，这里选择的递归的前序遍历。

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
        if(p==null&&q==null) return true;
        if(p!=null&&q==null||p==null&&q!=null) return false;
        if(p.val!=q.val) return false;
        else{return isSameTree(p.left,q.left)&&isSameTree(p.right,q.right);}
    }
}