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[] nums, int target) { if(nums.length<2) return nums; int[] arr=new int[2]; Map<Integer,Integer> map=new HashMap<Integer,Integer>(); for(int i=0;i<nums.length;i++) { if(!map.containsKey(nums[i])){ map.put(nums[i],i); } if(map.containsKey(target-nums[i])&&i!=map.get(target-nums[i])) { arr[0]=map.get(target-nums[i]); arr[1]=i; return arr; } } return arr; } }
如果有更好解法的朋友欢迎评论。
原文：http://www.cnblogs.com/dailinfu/p/6985666.html