🧑💻 算法学习 · Dynamic Programming
动态规划 (Dynamic Programming)
概述
难度:困难 (Hard)
分类:Algorithm Paradigm / 算法思想
动态规划是一种将复杂问题分解为更小子问题的算法思想,通过存储子问题避免重复计算。
DP is an algorithm paradigm that decomposes complex problems into subproblems, storing results to avoid redundant computation.
算法原理
中文:最优子结构 + 重叠子问题 = 动态规划。通过记忆化或自底向上避免重复计算。
English: Optimal substructure + overlapping subproblems = DP. Use memoization or bottom-up to avoid redundant computation.
复杂度分析
| 类型 | 复杂度 |
|---|---|
| 时间复杂度 | O(n) |
| 空间复杂度 | O(n) 或 O(1) |
代码实现
# 以斐波那契为例
def fib_dp(n):
if n <= 1:
return n
dp = [0] * (n + 1)
dp[1] = 1
for i in range(2, n + 1):
dp[i] = dp[i-1] + dp[i-2]
return dp[n]
# 空间优化版本
def fib_optimized(n):
if n <= 1:
return n
prev, curr = 0, 1
for _ in range(2, n + 1):
prev, curr = curr, prev + curr
return curr
每日练习
- 完成算法实现
- 分析算法复杂度
- 思考:算法的适用场景和局限性
相关阅读:算法专栏
💡 学习建议:算法学习重在理解思想,多写多练是关键。 💡 Learning tip: Algorithm learning is about understanding the core idea. Practice makes perfect.