@@ -0,0 +1,747 @@
+package leetcode;%0A%0A/**%0A * https://oj.leetcode.com/problems/symmetric-tree/%0A */%0Apublic class Problem101 %7B%0A    public static class TreeNode %7B%0A        int val;%0A        TreeNode left;%0A        TreeNode right;%0A%0A        TreeNode(int x) %7B%0A            val = x;%0A        %7D%0A    %7D%0A%0A    public boolean isSymmetric(TreeNode root) %7B%0A        if (root == null) %7B%0A            return true;%0A        %7D%0A        return isSymmetric(root.left, root.right);%0A    %7D%0A    %0A    private boolean isSymmetric(TreeNode p, TreeNode q) %7B%0A        if (p == null && q == null) %7B%0A            return true;%0A        %7D else if (p != null && q != null && p.val == q.val) %7B%0A            return isSymmetric(p.left, q.right) && isSymmetric(p.right, q.left);%0A        %7D%0A        return false;%0A    %7D%0A%7D%0A

Solve problem 101