From dbbfcf9e450a80d5a406d582f6b0b8700ae79ce3 Mon Sep 17 00:00:00 2001
From: dingjiawen <745518019@qq.com>
Date: Mon, 23 May 2022 22:50:29 +0800
Subject: [PATCH] =?UTF-8?q?leecode=E6=9B=B4=E6=96=B0?=
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---
 Leecode/src/main/java/sort/ThreeSum.java | 62 ++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/Leecode/src/main/java/sort/ThreeSum.java b/Leecode/src/main/java/sort/ThreeSum.java
index 4cd21ca..79675a9 100644
--- a/Leecode/src/main/java/sort/ThreeSum.java
+++ b/Leecode/src/main/java/sort/ThreeSum.java
@@ -89,6 +89,68 @@ public class ThreeSum {
             }
 
 
+        }
+
+
+        return parentList;
+
+    }
+
+    //更简洁一点的思路
+    public static List<List<Integer>> threeSum1(int[] nums) {
+
+        List<List<Integer>> parentList = new ArrayList<>();
+
+        if (nums.length < 3) {
+            return parentList;
+        }
+        //先排序
+        Arrays.sort(nums);
+
+        //后累加
+        //第一个数的索引i
+        for (int i = 0; i < nums.length; i++) {
+
+            if(nums[i]>0) break;
+
+            //为了避免这一次和前一次重复
+            if (i > 0 && nums[i] == nums[i - 1]) {
+                continue;
+            }
+
+            //第三个数的索引k
+            int k = nums.length - 1;
+
+            //第二个数的索引
+            int j=i+1;
+
+
+
+            //开始遍历
+            while(j<k){
+                //三数之和
+                int sum = nums[i]+nums[j]+nums[k];
+                if(sum<0){
+                    //不够了
+                    j++;
+
+                }else if(sum>0){
+                    //太多了
+                    k--;
+
+                }else {
+                    parentList.add(new ArrayList<Integer>(Arrays.asList(nums[i],nums[j],nums[k])));
+                    //为了避免和上一次重复
+                    while (j<k&&nums[j+1]==nums[j]){j++;} //相同中间数只能出现一次
+                    while (j<k&&nums[k-1]==nums[k]){k--;}  //相同最大数只能出现一次
+                    j++;
+                    k--;
+                }
+            }
+
+
+
+
         }