refactor: use Package.swift to define executable task

codes/swift/Package.swift

@@ -0,0 +1,18 @@
+// swift-tools-version: 5.7
+
+import PackageDescription
+
+let package = Package(
+    name: "HelloAlgo",
+    products: [
+        .executable(name: "time_complexity", targets: ["time_complexity"]),
+        .executable(name: "worst_best_time_complexity", targets: ["worst_best_time_complexity"]),
+        .executable(name: "space_complexity", targets: ["space_complexity"]),
+    ],
+    targets: [
+        .target(name: "utils", path: "utils"),
+        .executableTarget(name: "time_complexity", path: "chapter_computational_complexity", sources: ["time_complexity.swift"]),
+        .executableTarget(name: "worst_best_time_complexity", path: "chapter_computational_complexity", sources: ["worst_best_time_complexity.swift"]),
+        .executableTarget(name: "space_complexity", dependencies: ["utils"], path: "chapter_computational_complexity", sources: ["space_complexity.swift"]),
+    ]
+)

codes/swift/chapter_computational_complexity/space_complexity.swift

@@ -4,82 +4,7 @@
  * Author: nuomi1 (nuomi1@qq.com)
  */
 
-class ListNode {
+import utils
-    var val: Int
-    var next: ListNode?
-
-    init(x: Int) {
-        val = x
-    }
-}
-
-class TreeNode {
-    var val: Int // 结点值
-    var height: Int // 结点高度
-    var left: TreeNode? // 左子结点引用
-    var right: TreeNode? // 右子结点引用
-
-    init(x: Int) {
-        val = x
-        height = 0
-    }
-}
-
-enum PrintUtil {
-    private class Trunk {
-        var prev: Trunk?
-        var str: String
-
-        init(prev: Trunk?, str: String) {
-            self.prev = prev
-            self.str = str
-        }
-    }
-
-    static func printTree(root: TreeNode?) {
-        printTree(root: root, prev: nil, isLeft: false)
-    }
-
-    private static func printTree(root: TreeNode?, prev: Trunk?, isLeft: Bool) {
-        if root == nil {
-            return
-        }
-
-        var prevStr = "    "
-        let trunk = Trunk(prev: prev, str: prevStr)
-
-        printTree(root: root?.right, prev: trunk, isLeft: true)
-
-        if prev == nil {
-            trunk.str = "———"
-        } else if isLeft {
-            trunk.str = "/———"
-            prevStr = "   |"
-        } else {
-            trunk.str = "\\———"
-            prev?.str = prevStr
-        }
-
-        showTrunks(p: trunk)
-        print(" \(root!.val)")
-
-        if prev != nil {
-            prev?.str = prevStr
-        }
-        trunk.str = "   |"
-
-        printTree(root: root?.left, prev: trunk, isLeft: false)
-    }
-
-    private static func showTrunks(p: Trunk?) {
-        if p == nil {
-            return
-        }
-
-        showTrunks(p: p?.prev)
-        print(p!.str, terminator: "")
-    }
-}
 
 // 函数
 @discardableResult
@@ -153,8 +78,10 @@ func buildTree(n: Int) -> TreeNode? {
     return root
 }
 
-// Driver Code
+@main
-func main() {
+enum SpaceComplexity {
+    // Driver Code
+    static func main() {
         let n = 5
         // 常数阶
         constant(n: n)
@@ -167,6 +94,5 @@ func main() {
         // 指数阶
         let root = buildTree(n: n)
         PrintUtil.printTree(root: root)
+    }
 }
-
-main()

codes/swift/chapter_computational_complexity/time_complexity.swift

@@ -131,7 +131,9 @@ func factorialRecur(n: Int) -> Int {
     return count
 }
 
-func main() {
+@main
+enum TimeComplexity {
+    static func main() {
         // 可以修改 n 运行，体会一下各种复杂度的操作数量变化趋势
         let n = 8
         print("输入数据大小 n =", n)
@@ -165,6 +167,5 @@ func main() {
 
         count = factorialRecur(n: n)
         print("阶乘阶（递归实现）的计算操作数量 =", count)
+    }
 }
-
-main()

codes/swift/chapter_computational_complexity/worst_best_time_complexity.swift

@@ -23,8 +23,10 @@ func findOne(nums: [Int]) -> Int {
     return -1
 }
 
-// Driver Code
+@main
-func main() {
+enum WorstBestTimeComplexity {
+    // Driver Code
+    static func main() {
         for _ in 0 ..< 10 {
             let n = 100
             let nums = randomNumbers(n: n)
@@ -32,6 +34,5 @@ func main() {
             print("数组 [ 1, 2, ..., n ] 被打乱后 =", nums)
             print("数字 1 的索引为", index)
         }
+    }
 }
-
-main()

codes/swift/utils/ListNode.swift

@@ -0,0 +1,14 @@
+/*
+ * File: ListNode.swift
+ * Created Time: 2023-01-02
+ * Author: nuomi1 (nuomi1@qq.com)
+ */
+
+public class ListNode {
+    public var val: Int // 结点值
+    public var next: ListNode? // 后继结点引用
+
+    public init(x: Int) {
+        val = x
+    }
+}

codes/swift/utils/PrintUtil.swift

@@ -0,0 +1,61 @@
+/*
+ * File: PrintUtil.swift
+ * Created Time: 2023-01-02
+ * Author: nuomi1 (nuomi1@qq.com)
+ */
+
+public enum PrintUtil {
+    private class Trunk {
+        var prev: Trunk?
+        var str: String
+
+        init(prev: Trunk?, str: String) {
+            self.prev = prev
+            self.str = str
+        }
+    }
+
+    public static func printTree(root: TreeNode?) {
+        printTree(root: root, prev: nil, isLeft: false)
+    }
+
+    private static func printTree(root: TreeNode?, prev: Trunk?, isLeft: Bool) {
+        if root == nil {
+            return
+        }
+
+        var prevStr = "    "
+        let trunk = Trunk(prev: prev, str: prevStr)
+
+        printTree(root: root?.right, prev: trunk, isLeft: true)
+
+        if prev == nil {
+            trunk.str = "———"
+        } else if isLeft {
+            trunk.str = "/———"
+            prevStr = "   |"
+        } else {
+            trunk.str = "\\———"
+            prev?.str = prevStr
+        }
+
+        showTrunks(p: trunk)
+        print(" \(root!.val)")
+
+        if prev != nil {
+            prev?.str = prevStr
+        }
+        trunk.str = "   |"
+
+        printTree(root: root?.left, prev: trunk, isLeft: false)
+    }
+
+    private static func showTrunks(p: Trunk?) {
+        if p == nil {
+            return
+        }
+
+        showTrunks(p: p?.prev)
+        print(p!.str, terminator: "")
+    }
+}

codes/swift/utils/TreeNode.swift

@@ -0,0 +1,17 @@
+/*
+ * File: TreeNode.swift
+ * Created Time: 2023-01-02
+ * Author: nuomi1 (nuomi1@qq.com)
+ */
+
+public class TreeNode {
+    public var val: Int // 结点值
+    public var height: Int // 结点高度
+    public var left: TreeNode? // 左子结点引用
+    public var right: TreeNode? // 右子结点引用
+
+    public init(x: Int) {
+        val = x
+        height = 0
+    }
+}