mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-25 22:16:29 +08:00
b2f0d4603d
* Add Ruby and Kotlin icons Add the avatar of @curtishd * Update README * Synchronize zh-hant and zh versions. * Translate the pythontutor blocks to traditional Chinese * Fix en/mkdocs.yml * Update the landing page of the en version. * Fix the Dockerfile * Refine the en landingpage * Fix en landing page * Reset the README.md
55 lines
No EOL
1.6 KiB
Kotlin
55 lines
No EOL
1.6 KiB
Kotlin
/**
|
||
* File: subset_sum_i_native.kt
|
||
* Created Time: 2024-01-25
|
||
* Author: curtishd (1023632660@qq.com)
|
||
*/
|
||
|
||
package chapter_backtracking.subset_sum_i_naive
|
||
|
||
/* 回溯演算法:子集和 I */
|
||
fun backtrack(
|
||
state: MutableList<Int>,
|
||
target: Int,
|
||
total: Int,
|
||
choices: IntArray,
|
||
res: MutableList<MutableList<Int>?>
|
||
) {
|
||
// 子集和等於 target 時,記錄解
|
||
if (total == target) {
|
||
res.add(state.toMutableList())
|
||
return
|
||
}
|
||
// 走訪所有選擇
|
||
for (i in choices.indices) {
|
||
// 剪枝:若子集和超過 target ,則跳過該選擇
|
||
if (total + choices[i] > target) {
|
||
continue
|
||
}
|
||
// 嘗試:做出選擇,更新元素和 total
|
||
state.add(choices[i])
|
||
// 進行下一輪選擇
|
||
backtrack(state, target, total + choices[i], choices, res)
|
||
// 回退:撤銷選擇,恢復到之前的狀態
|
||
state.removeAt(state.size - 1)
|
||
}
|
||
}
|
||
|
||
/* 求解子集和 I(包含重複子集) */
|
||
fun subsetSumINaive(nums: IntArray, target: Int): MutableList<MutableList<Int>?> {
|
||
val state = mutableListOf<Int>() // 狀態(子集)
|
||
val total = 0 // 子集和
|
||
val res = mutableListOf<MutableList<Int>?>() // 結果串列(子集串列)
|
||
backtrack(state, target, total, nums, res)
|
||
return res
|
||
}
|
||
|
||
/* Driver Code */
|
||
fun main() {
|
||
val nums = intArrayOf(3, 4, 5)
|
||
val target = 9
|
||
val res = subsetSumINaive(nums, target)
|
||
|
||
println("輸入陣列 nums = ${nums.contentToString()}, target = $target")
|
||
println("所有和等於 $target 的子集 res = $res")
|
||
println("請注意,該方法輸出的結果包含重複集合")
|
||
} |