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Add build script for Swift.

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This commit is contained in:
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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63
docs/chapter_computational_complexity/space_complexity.md
View File

@@ -665,22 +665,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 常数阶 */
func constant(n: Int) {
// 常量、变量、对象占用 O(1) 空间
let a = 0
var b = 0
let nums = Array(repeating: 0, count: 10000)
let node = ListNode(x: 0)
// 循环中的变量占用 O(1) 空间
for _ in 0 ..< n {
let c = 0
}
// 循环中的函数占用 O(1) 空间
for _ in 0 ..< n {
function()
}
}
[class]{}-[func]{constant}
```
=== "Zig"
@@ -797,15 +782,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 线性阶 */
func linear(n: Int) {
// 长度为 n 的数组占用 O(n) 空间
let nums = Array(repeating: 0, count: n)
// 长度为 n 的列表占用 O(n) 空间
let nodes = (0 ..< n).map { ListNode(x: $0) }
// 长度为 n 的哈希表占用 O(n) 空间
let map = Dictionary(uniqueKeysWithValues: (0 ..< n).map { ($0, "\($0)") })
}
[class]{}-[func]{linear}
```
=== "Zig"
@@ -901,14 +878,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 线性阶（递归实现） */
func linearRecur(n: Int) {
print("递归 n = \(n)")
if n == 1 {
return
}
linearRecur(n: n - 1)
}
[class]{}-[func]{linearRecur}
```
=== "Zig"
@@ -1004,11 +974,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 平方阶 */
func quadratic(n: Int) {
// 二维列表占用 O(n^2) 空间
let numList = Array(repeating: Array(repeating: 0, count: n), count: n)
}
[class]{}-[func]{quadratic}
```
=== "Zig"
@@ -1100,15 +1066,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 平方阶（递归实现） */
func quadraticRecur(n: Int) -> Int {
if n <= 0 {
return 0
}
// 数组 nums 长度为 n, n-1, ..., 2, 1
let nums = Array(repeating: 0, count: n)
return quadraticRecur(n: n - 1)
}
[class]{}-[func]{quadraticRecur}
```
=== "Zig"
@@ -1199,16 +1157,7 @@ $$
=== "Swift"
```swift title="space_complexity.swift"
/* 指数阶（建立满二叉树） */
func buildTree(n: Int) -> TreeNode? {
if n == 0 {
return nil
}
let root = TreeNode(x: 0)
root.left = buildTree(n: n - 1)
root.right = buildTree(n: n - 1)
return root
}
[class]{}-[func]{buildTree}
```
=== "Zig"

25
docs/chapter_computational_complexity/space_time_tradeoff.md
View File

@@ -108,17 +108,7 @@ comments: true
=== "Swift"
```swift title="leetcode_two_sum.swift"
func twoSumBruteForce(nums: [Int], target: Int) -> [Int] {
// 两层循环，时间复杂度 O(n^2)
for i in nums.indices.dropLast() {
for j in nums.indices.dropFirst(i + 1) {
if nums[i] + nums[j] == target {
return [i, j]
}
}
}
return [0]
}
[class]{}-[func]{twoSumBruteForce}
```
=== "Zig"
@@ -229,18 +219,7 @@ comments: true
=== "Swift"
```swift title="leetcode_two_sum.swift"
func twoSumHashTable(nums: [Int], target: Int) -> [Int] {
// 辅助哈希表，空间复杂度 O(n)
var dic: [Int: Int] = [:]
// 单层循环，时间复杂度 O(n)
for i in nums.indices {
if let j = dic[target - nums[i]] {
return [j, i]
}
dic[nums[i]] = i
}
return [0]
}
[class]{}-[func]{twoSumHashTable}
```
=== "Zig"

127
docs/chapter_computational_complexity/time_complexity.md
View File

@@ -868,15 +868,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 常数阶 */
func constant(n: Int) -> Int {
var count = 0
let size = 100000
for _ in 0 ..< size {
count += 1
}
return count
}
[class]{}-[func]{constant}
```
=== "Zig"
@@ -971,14 +963,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 线性阶 */
func linear(n: Int) -> Int {
var count = 0
for _ in 0 ..< n {
count += 1
}
return count
}
[class]{}-[func]{linear}
```
=== "Zig"
@@ -1078,15 +1063,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 线性阶（遍历数组） */
func arrayTraversal(nums: [Int]) -> Int {
var count = 0
// 循环次数与数组长度成正比
for _ in nums {
count += 1
}
return count
}
[class]{}-[func]{arrayTraversal}
```
=== "Zig"
@@ -1191,17 +1168,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 平方阶 */
func quadratic(n: Int) -> Int {
var count = 0
// 循环次数与数组长度成平方关系
for _ in 0 ..< n {
for _ in 0 ..< n {
count += 1
}
}
return count
}
[class]{}-[func]{quadratic}
```
=== "Zig"
@@ -1341,24 +1308,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 平方阶（冒泡排序） */
func bubbleSort(nums: inout [Int]) -> Int {
var count = 0 // 计数器
// 外循环：待排序元素数量为 n-1, n-2, ..., 1
for i in sequence(first: nums.count - 1, next: { $0 > 0 + 1 ? $0 - 1 : nil }) {
// 内循环：冒泡操作
for j in 0 ..< i {
if nums[j] > nums[j + 1] {
// 交换 nums[j] 与 nums[j + 1]
let tmp = nums[j]
nums[j] = nums[j + 1]
nums[j + 1] = tmp
count += 3 // 元素交换包含 3 个单元操作
}
}
}
return count
}
[class]{}-[func]{bubbleSort}
```
=== "Zig"
@@ -1485,20 +1435,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 指数阶（循环实现） */
func exponential(n: Int) -> Int {
var count = 0
var base = 1
// cell 每轮一分为二，形成数列 1, 2, 4, 8, ..., 2^(n-1)
for _ in 0 ..< n {
for _ in 0 ..< base {
count += 1
}
base *= 2
}
// count = 1 + 2 + 4 + 8 + .. + 2^(n-1) = 2^n - 1
return count
}
[class]{}-[func]{exponential}
```
=== "Zig"
@@ -1594,13 +1531,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 指数阶（递归实现） */
func expRecur(n: Int) -> Int {
if n == 1 {
return 1
}
return expRecur(n: n - 1) + expRecur(n: n - 1) + 1
}
[class]{}-[func]{expRecur}
```
=== "Zig"
@@ -1698,16 +1629,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 对数阶（循环实现） */
func logarithmic(n: Int) -> Int {
var count = 0
var n = n
while n > 1 {
n = n / 2
count += 1
}
return count
}
[class]{}-[func]{logarithmic}
```
=== "Zig"
@@ -1799,13 +1721,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 对数阶（递归实现） */
func logRecur(n: Int) -> Int {
if n <= 1 {
return 0
}
return logRecur(n: n / 2) + 1
}
[class]{}-[func]{logRecur}
```
=== "Zig"
@@ -1907,17 +1823,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 线性对数阶 */
func linearLogRecur(n: Double) -> Int {
if n <= 1 {
return 1
}
var count = linearLogRecur(n: n / 2) + linearLogRecur(n: n / 2)
for _ in 0 ..< Int(n) {
count += 1
}
return count
}
[class]{}-[func]{linearLogRecur}
```
=== "Zig"
@@ -2032,18 +1938,7 @@ $$
=== "Swift"
```swift title="time_complexity.swift"
/* 阶乘阶（递归实现） */
func factorialRecur(n: Int) -> Int {
if n == 0 {
return 1
}
var count = 0
// 从 1 个分裂出 n 个
for _ in 0 ..< n {
count += factorialRecur(n: n - 1)
}
return count
}
[class]{}-[func]{factorialRecur}
```
=== "Zig"