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Add build script for Swift.

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krahets
2023-02-08 20:30:05 +08:00
parent 05f0054005
commit 38751cc5f5
25 changed files with 128 additions and 1223 deletions
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34
codes/swift/chapter_sorting/quick_sort.swift
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@@ -12,8 +12,8 @@ func swap(nums: inout [Int], i: Int, j: Int) {
}
/* 快速排序类 */
// 快速排序类-哨兵划分
func quickSortPartition(nums: inout [Int], left: Int, right: Int) -> Int {
/* 哨兵划分 */
func partition(nums: inout [Int], left: Int, right: Int) -> Int {
// 以 nums[left] 作为基准数
var i = left
var j = right
@@ -30,22 +30,23 @@ func quickSortPartition(nums: inout [Int], left: Int, right: Int) -> Int {
return i // 返回基准数的索引
}
// 快速排序类-快速排序
/* 快速排序 */
func quickSort(nums: inout [Int], left: Int, right: Int) {
// 子数组长度为 1 时终止递归
if left >= right {
return
}
// 哨兵划分
let pivot = quickSortPartition(nums: &nums, left: left, right: right)
let pivot = partition(nums: &nums, left: left, right: right)
// 递归左子数组、右子数组
quickSort(nums: &nums, left: left, right: pivot - 1)
quickSort(nums: &nums, left: pivot + 1, right: right)
}
/* 快速排序类（中位基准数优化） */
// 快速排序类（中位基准数优化）-选取三个元素的中位数
func quickSortMedianThree(nums: [Int], left: Int, mid: Int, right: Int) -> Int {
/* 选取三个元素的中位数 */
func medianThree(nums: [Int], left: Int, mid: Int, right: Int) -> Int {
if (nums[left] < nums[mid]) != (nums[left] < nums[right]) {
return left
} else if (nums[mid] < nums[left]) != (nums[mid] < nums[right]) {
@@ -55,42 +56,37 @@ func quickSortMedianThree(nums: [Int], left: Int, mid: Int, right: Int) -> Int {
}
}
// 快速排序类（中位基准数优化）-哨兵划分（三数取中值）
func quickSortMedianPartition(nums: inout [Int], left: Int, right: Int) -> Int {
/* 哨兵划分（三数取中值） */
func partitionMedian(nums: inout [Int], left: Int, right: Int) -> Int {
// 选取三个候选元素的中位数
let med = quickSortMedianThree(nums: nums, left: left, mid: (left + right) / 2, right: right)
let med = medianThree(nums: nums, left: left, mid: (left + right) / 2, right: right)
// 将中位数交换至数组最左端
swap(nums: &nums, i: left, j: med)
return quickSortPartition(nums: &nums, left: left, right: right)
return partition(nums: &nums, left: left, right: right)
}
// 快速排序类（中位基准数优化）-快速排序
/* 快速排序（中位基准数优化） */
func quickSortMedian(nums: inout [Int], left: Int, right: Int) {
// 子数组长度为 1 时终止递归
if left >= right {
return
}
// 哨兵划分
let pivot = quickSortMedianPartition(nums: &nums, left: left, right: right)
let pivot = partitionMedian(nums: &nums, left: left, right: right)
// 递归左子数组、右子数组
quickSortMedian(nums: &nums, left: left, right: pivot - 1)
quickSortMedian(nums: &nums, left: pivot + 1, right: right)
}
/* 快速排序类（尾递归优化） */
// 快速排序类（尾递归优化）-哨兵划分
func quickSortTailCallPartition(nums: inout [Int], left: Int, right: Int) -> Int {
quickSortPartition(nums: &nums, left: left, right: right)
}
// 快速排序类（尾递归优化）-快速排序（尾递归优化）
/* 快速排序（尾递归优化） */
func quickSortTailCall(nums: inout [Int], left: Int, right: Int) {
var left = left
var right = right
// 子数组长度为 1 时终止
while left < right {
// 哨兵划分操作
let pivot = quickSortTailCallPartition(nums: &nums, left: left, right: right)
let pivot = partition(nums: &nums, left: left, right: right)
// 对两个子数组中较短的那个执行快排
if (pivot - left) < (right - pivot) {
quickSortTailCall(nums: &nums, left: left, right: pivot - 1) // 递归排序左子数组