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feat: Revised the book (#978)

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* 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
This commit is contained in:
Yudong Jin
2023-12-02 06:21:34 +08:00
committed by GitHub
parent b824d149cb
commit e720aa2d24
404 changed files with 1537 additions and 1558 deletions
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6
codes/swift/chapter_searching/binary_search.swift
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@@ -24,9 +24,9 @@ func binarySearch(nums: [Int], target: Int) -> Int {
return -1
}
/* 二分查找（左闭右开） */
/* 二分查找（左闭右开区间） */
func binarySearchLCRO(nums: [Int], target: Int) -> Int {
// 初始化左闭右开 [0, n) ，即 i, j 分别指向数组首元素、尾元素+1
// 初始化左闭右开区间 [0, n) ，即 i, j 分别指向数组首元素、尾元素+1
var i = 0
var j = nums.count
// 循环，当搜索区间为空时跳出（当 i = j 时为空）
@@ -55,7 +55,7 @@ enum BinarySearch {
var index = binarySearch(nums: nums, target: target)
print("目标元素 6 的索引 = \(index)")
/* 二分查找（左闭右开） */
/* 二分查找（左闭右开区间） */
index = binarySearchLCRO(nums: nums, target: target)
print("目标元素 6 的索引 = \(index)")
}

6
codes/swift/chapter_searching/two_sum.swift
View File

@@ -6,7 +6,7 @@
/* 方法一：暴力枚举 */
func twoSumBruteForce(nums: [Int], target: Int) -> [Int] {
// 两层循环，时间复杂度 O(n^2)
// 两层循环，时间复杂度为 O(n^2)
for i in nums.indices.dropLast() {
for j in nums.indices.dropFirst(i + 1) {
if nums[i] + nums[j] == target {
@@ -19,9 +19,9 @@ func twoSumBruteForce(nums: [Int], target: Int) -> [Int] {
/* 方法二：辅助哈希表 */
func twoSumHashTable(nums: [Int], target: Int) -> [Int] {
// 辅助哈希表，空间复杂度 O(n)
// 辅助哈希表，空间复杂度为 O(n)
var dic: [Int: Int] = [:]
// 单层循环，时间复杂度 O(n)
// 单层循环，时间复杂度为 O(n)
for i in nums.indices {
if let j = dic[target - nums[i]] {
return [j, i]