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* 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
/**
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* File: subset_sum_i_native.kt
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* Created Time: 2024-01-25
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* Author: curtishd (1023632660@qq.com)
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*/
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package chapter_backtracking.subset_sum_i_naive
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/* 回溯演算法:子集和 I */
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fun backtrack(
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state: MutableList<Int>,
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target: Int,
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total: Int,
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choices: IntArray,
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res: MutableList<MutableList<Int>?>
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) {
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// 子集和等於 target 時,記錄解
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if (total == target) {
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res.add(state.toMutableList())
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return
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}
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// 走訪所有選擇
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for (i in choices.indices) {
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// 剪枝:若子集和超過 target ,則跳過該選擇
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if (total + choices[i] > target) {
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continue
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}
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// 嘗試:做出選擇,更新元素和 total
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state.add(choices[i])
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// 進行下一輪選擇
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backtrack(state, target, total + choices[i], choices, res)
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// 回退:撤銷選擇,恢復到之前的狀態
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state.removeAt(state.size - 1)
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}
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}
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/* 求解子集和 I(包含重複子集) */
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fun subsetSumINaive(nums: IntArray, target: Int): MutableList<MutableList<Int>?> {
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val state = mutableListOf<Int>() // 狀態(子集)
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val total = 0 // 子集和
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val res = mutableListOf<MutableList<Int>?>() // 結果串列(子集串列)
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backtrack(state, target, total, nums, res)
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return res
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}
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/* Driver Code */
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fun main() {
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val nums = intArrayOf(3, 4, 5)
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val target = 9
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val res = subsetSumINaive(nums, target)
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println("輸入陣列 nums = ${nums.contentToString()}, target = $target")
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println("所有和等於 $target 的子集 res = $res")
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println("請注意,該方法輸出的結果包含重複集合")
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} |