首页 > 代码库 > [Leetcode] 3Sum
[Leetcode] 3Sum
Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.
Note:
- Elements in a triplet (a,b,c) must be in non-descending order. (ie, a ≤ b ≤ c)
- The solution set must not contain duplicate triplets.
For example, given array S = {-1 0 1 2 -1 -4}, A solution set is: (-1, 0, 1) (-1, -1, 2)
Solution:
1 public class Solution { 2 public List<List<Integer>> threeSum(int[] num) { 3 List<List<Integer>> result = new ArrayList<List<Integer>>(); 4 if (num.length < 3) 5 return result; 6 Arrays.sort(num); 7 for (int i = 0; i < num.length - 2; ++i) { 8 if (i > 0 && num[i] == num[i - 1]) 9 continue;10 int a = num[i];11 int low = i + 1;12 int high = num.length - 1;13 while (low < high) {14 if (-a == num[low] + num[high]) {15 List<Integer> temp = new ArrayList<Integer>();16 temp.add(a);17 temp.add(num[low]);18 temp.add(num[high]);19 result.add(temp);20 low++;21 high--;22 while (low < high && num[low] == num[low - 1])23 low++;24 while (low < high && num[high] == num[high + 1])25 high--;26 } else if (-a > num[low] + num[high])27 low++;28 else29 high--;30 }31 }32 return result;33 }34 }
注意:如果current value=http://www.mamicode.com/=previous value,需要跳过当前值。
[Leetcode] 3Sum
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。