From f7adb3ab9f6bfd06489ee006237215d19db5a514 Mon Sep 17 00:00:00 2001
From: Sainnhe Park <i@sainnhe.dev>
Date: Fri, 10 Feb 2023 10:01:40 +0800
Subject: [PATCH] Update stock notes

---
 notes/src/stock.md | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/notes/src/stock.md b/notes/src/stock.md
index 6f31fbc..f84347a 100644
--- a/notes/src/stock.md
+++ b/notes/src/stock.md
@@ -16,3 +16,18 @@
   - `dp[0][0] = -prices[0]`
   - `dp[0][1] = 0`
 - 遍历顺序：从前往后
+
+## [123.买卖股票的最佳时机III](https://leetcode.cn/problems/best-time-to-buy-and-sell-stock-iii/)
+
+- `dp[i][j][k]` 是第 `i` 笔交易中，第 `j` 天，是否持有股票时的总资产
+- 递推公式：
+  - `dp[0][i][0] = max(dp[0][i - 1][0], -prices[i])`
+  - `dp[0][i][1] = max(dp[0][i - 1][1], dp[0][i][0] + prices[i])`
+  - `dp[1][i][0] = max(dp[1][i - 1][0], dp[0][i - 1][1] - prices[i])`
+  - `dp[1][i][1] = max(dp[1][i - 1][1], dp[0][i - 1][0] + prices[i])`
+- 初始化：
+  - `dp[i][0][0] = -prices[0]`
+  - `dp[i][0][1] = 0`
+- 遍历顺序：
+  - 先遍历 `i`
+  - 再遍历 `j` 和 `k`