From 406d17051a2493b8b4d6b40a8588c7ef998a7f17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E6=98=A0=E8=BE=89?= <3385297953@qq.com>
Date: Tue, 14 Oct 2025 19:35:12 +0800
Subject: [PATCH] 2025.10.14

---
 ..._\351\231\210\346\230\240\350\276\211.cpp" | 19 ++++++++++++++
 ..._\351\231\210\346\230\240\350\276\211.cpp" | 10 +++++++
 ..._\351\231\210\346\230\240\350\276\211.cpp" | 14 ++++++++++
 ..._\351\231\210\346\230\240\350\276\211.cpp" | 26 +++++++++++++++++++
 ..._\351\231\210\346\230\240\350\276\211.cpp" | 23 ++++++++++++++++
 5 files changed, 92 insertions(+)
 create mode 100644 "topic03/submit/LC1186_\351\231\210\346\230\240\350\276\211.cpp"
 create mode 100644 "topic03/submit/LC1480_\351\231\210\346\230\240\350\276\211.cpp"
 create mode 100644 "topic03/submit/LC53_\351\231\210\346\230\240\350\276\211.cpp"
 create mode 100644 "topic03/submit/LC560_\351\231\210\346\230\240\350\276\211.cpp"
 create mode 100644 "topic03/submit/LC918_\351\231\210\346\230\240\350\276\211.cpp"

diff --git "a/topic03/submit/LC1186_\351\231\210\346\230\240\350\276\211.cpp" "b/topic03/submit/LC1186_\351\231\210\346\230\240\350\276\211.cpp"
new file mode 100644
index 0000000..23aea85
--- /dev/null
+++ "b/topic03/submit/LC1186_\351\231\210\346\230\240\350\276\211.cpp"
@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int maximumSum(vector<int>& arr) {
+        int n=arr.size();
+        vector<int> left(n),right(n);
+        left[0]=arr[0],right[n-1]=arr[n-1];
+        int res=left[0];     
+         //像双指针解法
+        for(int i=1;i<n;++i){
+            left[i]=max(left[i-1],0)+arr[i];
+            right[n-i-1]=max(right[n-i],0)+arr[n-i-1];
+            res=max(res,left[i]);
+        }
+        for(int i=1;i<n-1;++i){
+            res=max(res,left[i-1]+right[i+1]);
+        }
+        return res;
+    }
+};
diff --git "a/topic03/submit/LC1480_\351\231\210\346\230\240\350\276\211.cpp" "b/topic03/submit/LC1480_\351\231\210\346\230\240\350\276\211.cpp"
new file mode 100644
index 0000000..5873368
--- /dev/null
+++ "b/topic03/submit/LC1480_\351\231\210\346\230\240\350\276\211.cpp"
@@ -0,0 +1,10 @@
+class Solution {
+public:
+    vector<int> runningSum(vector<int>& nums) {
+        int n = nums.size();
+        for(int i=1;i<n;i++){
+            nums[i]+=nums[i-1];
+        }
+        return nums;
+    }
+};
diff --git "a/topic03/submit/LC53_\351\231\210\346\230\240\350\276\211.cpp" "b/topic03/submit/LC53_\351\231\210\346\230\240\350\276\211.cpp"
new file mode 100644
index 0000000..c17279e
--- /dev/null
+++ "b/topic03/submit/LC53_\351\231\210\346\230\240\350\276\211.cpp"
@@ -0,0 +1,14 @@
+class Solution {
+public:
+    int maxSubArray(vector<int>& nums) {
+        int ans=INT_MIN;
+        int pre_sum=0;
+        int min_pre_sum=0;
+        for(int x:nums){
+            pre_sum += x;
+            ans=max(ans,pre_sum-min_pre_sum);
+            min_pre_sum=min(min_pre_sum,pre_sum);
+        }
+        return ans;
+    }
+};
diff --git "a/topic03/submit/LC560_\351\231\210\346\230\240\350\276\211.cpp" "b/topic03/submit/LC560_\351\231\210\346\230\240\350\276\211.cpp"
new file mode 100644
index 0000000..50c6647
--- /dev/null
+++ "b/topic03/submit/LC560_\351\231\210\346\230\240\350\276\211.cpp"
@@ -0,0 +1,26 @@
+class Solution {
+    public int subarraySum(int[] nums, int k) {
+        //假设索引i处的前缀和为preSum(i)(前缀和包含nums[i]的值)
+        //那么如果存在preSum(i)-k=preSum(j)--索引j处的前缀和(j < i）
+        //则说明存在一个 [j-1,... i]的子数组符合条件
+        //那么获取子数组的个数，等价于，获取preSum(i)-k=preSum(j) 出现的次数
+
+        //定义HashMap, key=preSum, value=preSum 出现的次数
+        Map<Integer, Integer> map = new HashMap<>();
+        //针对特殊case:nums=[1],k=1;nums=[1,2,3],k=6,map插入初始值0->1
+        //记录第一次出现某处索引preSum(i) = k,preSum(i) - k = 0,count=1
+        map.put(0, 1);
+        int preSum = 0;
+        int res = 0;
+        for (int i = 0; i < nums.length; i++) {
+            preSum += nums[i];
+            if (map.containsKey(preSum - k)) {
+                //如果存在满足：preSum(i)-k=preSum(j) 对应的preSum(j)，将preSum(j)出现的次数累加到res
+                res += map.get(preSum - k);
+            }
+            //将preSum加入map,preSum已经存在count就+1
+            map.put(preSum, map.getOrDefault(preSum, 0) + 1);
+        }
+        return res;
+    }
+}
diff --git "a/topic03/submit/LC918_\351\231\210\346\230\240\350\276\211.cpp" "b/topic03/submit/LC918_\351\231\210\346\230\240\350\276\211.cpp"
new file mode 100644
index 0000000..92a77c9
--- /dev/null
+++ "b/topic03/submit/LC918_\351\231\210\346\230\240\350\276\211.cpp"
@@ -0,0 +1,23 @@
+class Solution {
+public:
+    int maxSubarraySumCircular(vector<int>& nums) {
+        int n=nums.size();
+        vector<int>leftMax(n);
+        leftMax[0]=nums[0];
+        int leftSum=nums[0];
+        int pre=nums[0];
+        int res=nums[0];
+        for(int i=1;i<n;i++){
+            pre=max(pre+nums[i],nums[i]);
+            res=max(res,pre);
+            leftSum+=nums[i];   //kadena算法
+            leftMax[i]=max(leftMax[i-1],leftSum);
+        }
+        int rightSum=0;
+        for(int i=n-1;i>0;i--){
+            rightSum +=nums[i];
+            res=max(res,rightSum+leftMax[i-1]);
+        }
+        return res;
+    }
+};
-- 
Gitee