From 65c6c74cc457aabc87dd8d411a32a88121cab8bf Mon Sep 17 00:00:00 2001
From: Sainnhe Park <i@sainnhe.dev>
Date: Wed, 8 Feb 2023 12:20:15 +0800
Subject: [PATCH] Add dp

---
 notes/src/SUMMARY.md                   |  5 +++++
 notes/src/dynamic-programming-basic.md | 12 ++++++++++++
 notes/src/dynamic-programming.md       | 11 +++++++++++
 3 files changed, 28 insertions(+)
 create mode 100644 notes/src/dynamic-programming-basic.md
 create mode 100644 notes/src/dynamic-programming.md

diff --git a/notes/src/SUMMARY.md b/notes/src/SUMMARY.md
index b65a080..239ee94 100644
--- a/notes/src/SUMMARY.md
+++ b/notes/src/SUMMARY.md
@@ -51,6 +51,11 @@
 
 - [总结](./greedy.md)
 
+# 动态规划
+
+- [总结](./dynamic-programming.md)
+- [基础问题](./dynamic-programming-basic.md)
+
 # STL
 
 - [总结](./stl.md)
diff --git a/notes/src/dynamic-programming-basic.md b/notes/src/dynamic-programming-basic.md
new file mode 100644
index 0000000..b30ec73
--- /dev/null
+++ b/notes/src/dynamic-programming-basic.md
@@ -0,0 +1,12 @@
+# 基础问题
+
+## [509. 斐波那契数](https://leetcode.cn/problems/fibonacci-number/)
+
+1. `dp[i]` 是第 `i` 个斐波那契数的数值
+2. `dp[i] = dp[i - 1] + dp[i - 2]`
+3. `dp[0] = 0`, `dp[1] = 1`
+4. 从前向后遍历
+
+```cpp
+
+```
diff --git a/notes/src/dynamic-programming.md b/notes/src/dynamic-programming.md
new file mode 100644
index 0000000..506b827
--- /dev/null
+++ b/notes/src/dynamic-programming.md
@@ -0,0 +1,11 @@
+# 总结
+
+和贪心相似，从将问题划分为多个子问题，最后得出最终问题的解，但是区别在于每一步之间涉及到状态推导，下一步是基于上一步的结果和之前的记忆（也就是上上次，上上上次等的结果）经过一定逻辑推导得出的。
+
+分五步：
+
+1. 确定 `dp[i]` 是什么
+2. 确定递推公式
+3. `dp` 数组如何初始化
+4. 确定遍历顺序（从前向后还是从后向前）
+5. 推几个来验证