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//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.

/**
 * Definition for binary tree
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;

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//http://leetcode.com/2011/07/lowest-common-ancestor-of-a-binary-tree-part-i.html

public class LCA
{
	public static TreeNode findTheLowestCommonAncestor(TreeNode root, TreeNode nd1, TreeNode nd2) {

		if (root == null)
			return null;

		if (root == nd1 || root == nd2)

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/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }

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/**
 * Definition for binary tree
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Solution {

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/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }

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public class Solution {
    public int divide(int dividend, int divisor) {
        //http://www.lifeincode.net/programming/leetcode-divide-two-integers-java/
        long p = Math.abs((long)dividend);
        long q = Math.abs((long)divisor);
        
        int ret = 0;
        while (p >= q) {
            int counter = 0;
            while (p >= (q << counter)) {

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/*
Given a collection of integers that might contain duplicates, S, return all possible subsets.

Note:
Elements in a subset must be in non-descending order.
The solution set must not contain duplicate subsets.
For example,
If S = [1,2,2], a solution is:

[

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    public double findMedianSortedArrays(int A[], int B[]) {
        //http://www.cnblogs.com/tenosdoit/p/3554479.html
        int aLen = A.length;
        int bLen = B.length;
        
        if ((aLen + bLen) % 2 != 0) { //odd
            return findKth(A, B, (aLen + bLen) / 2, 0, aLen - 1, 0, bLen - 1);
        } else {
            return (findKth(A, B, (aLen + bLen) / 2 - 1, 0, aLen - 1, 0, bLen - 1)
                    + findKth(A, B, (aLen + bLen) / 2,   0, aLen - 1, 0, bLen - 1)) * (0.5);

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public int[] twoSum(int[] numbers, int target) {
        
        int[] ans = new int[2];
        HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();
        
        for (int i = 0; i < numbers.length; i++) {
            int num = numbers[i];
            if (map.containsKey(num)) {
                ans[0] = map.get(num) + 1;
                ans[1] = i + 1;

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    public int threeSumClosest(int[] num, int target) {
        http://www.programcreek.com/2013/02/leetcode-3sum-closest-java/
        int min = Integer.MAX_VALUE;
        int result = 0;
        Arrays.sort(num);
        
        for (int i = 0; i < num.length; i++) {
            int start = i + 1;
            int end = num.length - 1;