From 6567b4834a594a0e56923b617998513168c7a519 Mon Sep 17 00:00:00 2001
From: imp <imp07@qq.com>
Date: Sun, 5 Dec 2021 14:09:03 +0800
Subject: [PATCH] feat: add cpp solution to lc problem: No.188

---
 .../README.md                                 | 35 +++++++++++++++---
 .../README_EN.md                              | 36 ++++++++++++++++---
 .../Solution.cpp                              | 17 +++++++++
 3 files changed, 80 insertions(+), 8 deletions(-)
 create mode 100644 solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/Solution.cpp

diff --git a/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README.md b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README.md
index 758c821f27ae0..81e248c394058 100644
--- a/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README.md	
+++ b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README.md	
@@ -44,6 +44,17 @@
 
 <!-- 这里可写通用的实现逻辑 -->
 
+动态规划
+
+**dp[i][0]** 表示第 *i* 次买入后的收益，
+
+**dp[i][1]** 表示第 *i* 次卖出后的收益。
+
+状态转移方程：
+
+**dp[i][0] = max{dp[i][0], dp[i - 1][1] + prices[i]}**
+
+**dp[i][1] = max{dp[i][1], dp[i][0] + prices[i]}**
 <!-- tabs:start -->
 
 ### **Python3**
@@ -62,10 +73,26 @@
 
 ```
 
-### **...**
-
-```
-
+### **C++**
+
+```cpp
+class Solution {
+public:
+    int maxProfit(int k, vector<int>& prices) {
+        int dp[k + 1][2];
+        memset(dp, 0, sizeof(dp));
+        for(int i = 1; i <= k && !prices.empty(); ++i) {
+            dp[i][0] = -prices[0];
+        }
+        for(int i = 1; i < prices.size(); ++i) {
+            for(int j = 1; j <= k; ++j) {
+                dp[j][0] = max(dp[j][0], dp[j - 1][1] - prices[i]);
+                dp[j][1] = max(dp[j][1], dp[j][0] + prices[i]);
+            }
+        }
+        return dp[k][1];
+    }
+};
 ```
 
 <!-- tabs:end -->
diff --git a/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README_EN.md b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README_EN.md
index fbe242f8b18bc..4413f534bf123 100644
--- a/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README_EN.md	
+++ b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/README_EN.md	
@@ -39,6 +39,18 @@
 
 ## Solutions
 
+Dynamic programming
+
+**dp[i][0]** Indicates the income after the *i<sup>th* purchase,
+
+**dp[i][1]** Indicates the income after the *i<sup>th* sell.
+
+State transition equation:
+
+**dp[i][0] = max{dp[i][0], dp[i - 1][1] + prices[i]}**
+
+**dp[i][1] = max{dp[i][1], dp[i][0] + prices[i]}**
+
 <!-- tabs:start -->
 
 ### **Python3**
@@ -53,10 +65,26 @@
 
 ```
 
-### **...**
-
-```
-
+### **C++**
+
+```cpp
+class Solution {
+public:
+    int maxProfit(int k, vector<int>& prices) {
+        int dp[k + 1][2];
+        memset(dp, 0, sizeof(dp));
+        for(int i = 1; i <= k && !prices.empty(); ++i) {
+            dp[i][0] = -prices[0];
+        }
+        for(int i = 1; i < prices.size(); ++i) {
+            for(int j = 1; j <= k; ++j) {
+                dp[j][0] = max(dp[j][0], dp[j - 1][1] - prices[i]);
+                dp[j][1] = max(dp[j][1], dp[j][0] + prices[i]);
+            }
+        }
+        return dp[k][1];
+    }
+};
 ```
 
 <!-- tabs:end -->
diff --git a/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/Solution.cpp b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/Solution.cpp
new file mode 100644
index 0000000000000..1a68ed3a96c3d
--- /dev/null
+++ b/solution/0100-0199/0188.Best Time to Buy and Sell Stock IV/Solution.cpp	
@@ -0,0 +1,17 @@
+class Solution {
+public:
+    int maxProfit(int k, vector<int>& prices) {
+        int dp[k + 1][2];
+        memset(dp, 0, sizeof(dp));
+        for(int i = 1; i <= k && !prices.empty(); ++i) {
+            dp[i][0] = -prices[0];
+        }
+        for(int i = 1; i < prices.size(); ++i) {
+            for(int j = 1; j <= k; ++j) {
+                dp[j][0] = max(dp[j][0], dp[j - 1][1] - prices[i]);
+                dp[j][1] = max(dp[j][1], dp[j][0] + prices[i]);
+            }
+        }
+        return dp[k][1];
+    }
+};
\ No newline at end of file