lintcode56 - Two Sum - easy

import java.util.Arrays;

public class Solution {
    /*
     * @param numbers: An array of Integer
     * @param target: target = numbers[index1] + numbers[index2]
     * @return: [index1 + 1, index2 + 1] (index1 < index2)
     */
    public int[] twoSum(int[] numbers, int target) {
        // write your code here
        // mergesort- nlogn
        HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();

        // for loop with binary search -nlog
        for(int i = 0; i < numbers.length; i++){
            if(map.get(numbers[i]) != null){
                int[] twoIdx = {map.get(numbers[i]) +1 , i + 1};
                return twoIdx;
            }
            map.put(target - numbers[i], i);
        }
        int [] twoIdx = {};
        return twoIdx;
    }
    
}