001 Two Sum

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example:

Given nums = [2, 7, 11, 15], target = 9,Because nums[0] + nums[1] = 2 + 7 = 9,return [0, 1].

public class Solution {    public int[] twoSum(int[] numbers, int target) {    int[] result = new int[2];    Map<Integer, Integer> map = new HashMap<Integer, Integer>();    for (int i = 0; i < numbers.length; i++) {        if (map.containsKey(target - numbers[i])) {            result[1] = i ;            result[0] = map.get(target - numbers[i]);            return result;        }        map.put(numbers[i], i );    }    return result;}}