mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-27 04:06:28 +08:00
e720aa2d24
* Sync recent changes to the revised Word. * Revised the preface chapter * Revised the introduction chapter * Revised the computation complexity chapter * Revised the chapter data structure * Revised the chapter array and linked list * Revised the chapter stack and queue * Revised the chapter hashing * Revised the chapter tree * Revised the chapter heap * Revised the chapter graph * Revised the chapter searching * Reivised the sorting chapter * Revised the divide and conquer chapter * Revised the chapter backtacking * Revised the DP chapter * Revised the greedy chapter * Revised the appendix chapter * Revised the preface chapter doubly * Revised the figures
36 lines
829 B
Go
36 lines
829 B
Go
// File: climbing_stairs_backtrack.go
|
|
// Created Time: 2023-07-18
|
|
// Author: Reanon (793584285@qq.com)
|
|
|
|
package chapter_dynamic_programming
|
|
|
|
/* 回溯 */
|
|
func backtrack(choices []int, state, n int, res []int) {
|
|
// 当爬到第 n 阶时，方案数量加 1
|
|
if state == n {
|
|
res[0] = res[0] + 1
|
|
}
|
|
// 遍历所有选择
|
|
for _, choice := range choices {
|
|
// 剪枝：不允许越过第 n 阶
|
|
if state+choice > n {
|
|
continue
|
|
}
|
|
// 尝试：做出选择，更新状态
|
|
backtrack(choices, state+choice, n, res)
|
|
// 回退
|
|
}
|
|
}
|
|
|
|
/* 爬楼梯：回溯 */
|
|
func climbingStairsBacktrack(n int) int {
|
|
// 可选择向上爬 1 阶或 2 阶
|
|
choices := []int{1, 2}
|
|
// 从第 0 阶开始爬
|
|
state := 0
|
|
res := make([]int, 1)
|
|
// 使用 res[0] 记录方案数量
|
|
res[0] = 0
|
|
backtrack(choices, state, n, res)
|
|
return res[0]
|
|
}
|