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.
关于树结构自己没怎么看过,查了查遍历通常是:递归、stack
自己的解法
/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ publicclassSolution { publicbooleanisSameTree(TreeNode p, TreeNode q) { if (p == null && q == null) { returntrue; } if (p == null || q == null) { returnfalse; } if (p.val == q.val) { return isSameTree(p.left, q.left) && isSameTree(p.right, q.right); } returnfalse; } }