新增 0123.买卖股票的最佳时机III.md Go解法

problems/0123.买卖股票的最佳时机III.md

@@ -317,7 +317,38 @@ const maxProfit = prices => {
 };
 ```
 
+Go:
 
+> 版本一：
+```go
+// 买卖股票的最佳时机III 动态规划
+// 时间复杂度O(n) 空间复杂度O(n)
+func maxProfit(prices []int) int {
+    dp := make([][]int, len(prices))
+    status := make([]int, len(prices) * 4)
+    for i := range dp {
+        dp[i] = status[:4]
+        status = status[4:]
+    }
+    dp[0][0], dp[0][2] = -prices[0], -prices[0]
+
+    for i := 1; i < len(prices); i++ {
+        dp[i][0] = max(dp[i - 1][0], -prices[i])
+        dp[i][1] = max(dp[i - 1][1], dp[i - 1][0] + prices[i])
+        dp[i][2] = max(dp[i - 1][2], dp[i - 1][1] - prices[i])
+        dp[i][3] = max(dp[i - 1][3], dp[i - 1][2] + prices[i])
+    }
+
+    return dp[len(prices) - 1][3]
+}
+
+func max(a, b int) int {
+    if a > b {
+        return a
+    }
+    return b
+}
+```
 
 
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