【java】100. Same Tree

问题原文https://leetcode-cn.com/problems/same-tree/description/

 public boolean isSameTree(TreeNode p, TreeNode q) {
        if(p == null && q == null) return true;
        if(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);
        }
    }