From 5b3607c6a151b6fd6dd548c1b26f3f1fb8514047 Mon Sep 17 00:00:00 2001
From: Anmizi <1845513904@qq.com>
Date: Fri, 29 Apr 2022 23:18:33 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E6=94=B9=200040.=E7=BB=84=E5=90=88?=
 =?UTF-8?q?=E6=80=BB=E5=92=8CII.md?=
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---
 problems/0040.组合总和II.md | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/problems/0040.组合总和II.md b/problems/0040.组合总和II.md
index de13e031..34ac64e6 100644
--- a/problems/0040.组合总和II.md
+++ b/problems/0040.组合总和II.md
@@ -508,22 +508,27 @@ func backtracking(startIndex,sum,target int,candidates,trcak []int,res *[][]int)
  */
 var combinationSum2 = function(candidates, target) {
     const res = []; path = [], len = candidates.length;
-    candidates.sort();
+    candidates.sort((a,b)=>a-b);
     backtracking(0, 0);
     return res;
     function backtracking(sum, i) {
-        if (sum > target) return;
         if (sum === target) {
             res.push(Array.from(path));
             return;
         }
-        let f = -1;
         for(let j = i; j < len; j++) {
             const n = candidates[j];
-            if(n > target - sum || n === f) continue;
+            if(j > i && candidates[j] === candidates[j-1]){
+              //若当前元素和前一个元素相等
+              //则本次循环结束，防止出现重复组合
+              continue;
+            }
+            //如果当前元素值大于目标值-总和的值
+            //由于数组已排序，那么该元素之后的元素必定不满足条件
+            //直接终止当前层的递归
+            if(n > target - sum) break;
             path.push(n);
             sum += n;
-            f = n;
             backtracking(sum, j + 1);
             path.pop();
             sum -= n;