mirror of
https://github.com/krahets/hello-algo.git
synced 2025-11-04 14:18:20 +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
67 lines
1.4 KiB
Go
67 lines
1.4 KiB
Go
// File: coin_change.go
|
|
// Created Time: 2023-07-23
|
|
// Author: Reanon (793584285@qq.com)
|
|
|
|
package chapter_dynamic_programming
|
|
|
|
import "math"
|
|
|
|
/* 零钱兑换：动态规划 */
|
|
func coinChangeDP(coins []int, amt int) int {
|
|
n := len(coins)
|
|
max := amt + 1
|
|
// 初始化 dp 表
|
|
dp := make([][]int, n+1)
|
|
for i := 0; i <= n; i++ {
|
|
dp[i] = make([]int, amt+1)
|
|
}
|
|
// 状态转移：首行首列
|
|
for a := 1; a <= amt; a++ {
|
|
dp[0][a] = max
|
|
}
|
|
// 状态转移：其余行和列
|
|
for i := 1; i <= n; i++ {
|
|
for a := 1; a <= amt; a++ {
|
|
if coins[i-1] > a {
|
|
// 若超过目标金额，则不选硬币 i
|
|
dp[i][a] = dp[i-1][a]
|
|
} else {
|
|
// 不选和选硬币 i 这两种方案的较小值
|
|
dp[i][a] = int(math.Min(float64(dp[i-1][a]), float64(dp[i][a-coins[i-1]]+1)))
|
|
}
|
|
}
|
|
}
|
|
if dp[n][amt] != max {
|
|
return dp[n][amt]
|
|
}
|
|
return -1
|
|
}
|
|
|
|
/* 零钱兑换：动态规划 */
|
|
func coinChangeDPComp(coins []int, amt int) int {
|
|
n := len(coins)
|
|
max := amt + 1
|
|
// 初始化 dp 表
|
|
dp := make([]int, amt+1)
|
|
for i := 1; i <= amt; i++ {
|
|
dp[i] = max
|
|
}
|
|
// 状态转移
|
|
for i := 1; i <= n; i++ {
|
|
// 倒序遍历
|
|
for a := 1; a <= amt; a++ {
|
|
if coins[i-1] > a {
|
|
// 若超过目标金额，则不选硬币 i
|
|
dp[a] = dp[a]
|
|
} else {
|
|
// 不选和选硬币 i 这两种方案的较小值
|
|
dp[a] = int(math.Min(float64(dp[a]), float64(dp[a-coins[i-1]]+1)))
|
|
}
|
|
}
|
|
}
|
|
if dp[amt] != max {
|
|
return dp[amt]
|
|
}
|
|
return -1
|
|
}
|