100. Same Tree

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.

问题：给两棵二叉树判断它们是否相等，二叉树相等指两棵树在结构上一样，并且同一位置的结点所带的值相等。

思想：递归

boolean flag=true; public boolean isSameTree(TreeNode p, TreeNode q) { if(p==null&&q!=null||p!=null&&q==null) return flag=false; if(p!=null&&q!=null){ if(p.val!=q.val) { System.out.println("p.val="+p.val+"\tq.val="+q.val); return flag=false; }else{ //System.out.println("p.val="+p.val+"\tq.val="+q.val); isSameTree(p.left,q.left); isSameTree(p.right,q.right); } } return flag; }