feat: add swift implementation to lcp problem: No.10

lcp/LCP 10. 二叉树任务调度/README.md

@@ -204,6 +204,43 @@ function minimalExecTime(root: TreeNode | null): number {
 }
 ```
 
+#### Swift
+
+```swift
+/**
+* public class TreeNode {
+*     public var val: Int
+*     public var left: TreeNode?
+*     public var right: TreeNode?
+*     public init() { self.val = 0; self.left = nil; self.right = nil; }
+*     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }
+*     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {
+*         self.val = val
+*         self.left = left
+*         self.right = right
+*     }
+* }
+*/
+
+class Solution {
+    func minimalExecTime(_ root: TreeNode?) -> Double {
+        return dfs(root)[1]
+    }
+
+    private func dfs(_ root: TreeNode?) -> [Double] {
+        guard let root = root else { return [0.0, 0.0] }
+
+        let left = dfs(root.left)
+        let right = dfs(root.right)
+
+        let sum = left[0] + right[0] + Double(root.val)
+        let time = max(max(left[1], right[1]), (left[0] + right[0]) / 2) + Double(root.val)
+
+        return [sum, time]
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

lcp/LCP 10. 二叉树任务调度/Solution.swift

@@ -0,0 +1,32 @@
+/**
+* public class TreeNode {
+*     public var val: Int
+*     public var left: TreeNode?
+*     public var right: TreeNode?
+*     public init() { self.val = 0; self.left = nil; self.right = nil; }
+*     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }
+*     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {
+*         self.val = val
+*         self.left = left
+*         self.right = right
+*     }
+* }
+*/
+
+class Solution {
+    func minimalExecTime(_ root: TreeNode?) -> Double {
+        return dfs(root)[1]
+    }
+
+    private func dfs(_ root: TreeNode?) -> [Double] {
+        guard let root = root else { return [0.0, 0.0] }
+
+        let left = dfs(root.left)
+        let right = dfs(root.right)
+
+        let sum = left[0] + right[0] + Double(root.val)
+        let time = max(max(left[1], right[1]), (left[0] + right[0]) / 2) + Double(root.val)
+
+        return [sum, time]
+    }
+}