feat: add swift implementation to lcof2 problem: No.111

Author: klever34

lcof2/剑指 Offer II 111. 计算除法/README.md

@@ -292,6 +292,72 @@ func find(x int) int {
 }
 ```
 
+#### Swift
+
+```swift
+class Solution {
+    private var parent = [Int]()
+    private var weight = [Double]()
+    
+    func calcEquation(
+        _ equations: [[String]], 
+        _ values: [Double], 
+        _ queries: [[String]]
+    ) -> [Double] {
+        let n = equations.count
+        parent = Array(0..<(n * 2))
+        weight = Array(repeating: 1.0, count: n * 2)
+        
+        var map = [String: Int]()
+        var index = 0
+        
+        for i in 0..<n {
+            let a = equations[i][0]
+            let b = equations[i][1]
+            
+            if map[a] == nil {
+                map[a] = index
+                index += 1
+            }
+            if map[b] == nil {
+                map[b] = index
+                index += 1
+            }
+            
+            let pa = find(map[a]!)
+            let pb = find(map[b]!)
+            
+            if pa != pb {
+                parent[pa] = pb
+                weight[pa] = weight[map[b]!] * values[i] / weight[map[a]!]
+            }
+        }
+        
+        var result = [Double]()
+        
+        for query in queries {
+            let (c, d) = (query[0], query[1])
+            if let id1 = map[c], let id2 = map[d], find(id1) == find(id2) {
+                result.append(weight[id1] / weight[id2])
+            } else {
+                result.append(-1.0)
+            }
+        }
+        
+        return result
+    }
+    
+    private func find(_ x: Int) -> Int {
+        if parent[x] != x {
+            let origin = parent[x]
+            parent[x] = find(parent[x])
+            weight[x] *= weight[origin]
+        }
+        return parent[x]
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

lcof2/剑指 Offer II 111. 计算除法/Solution.swift

@@ -0,0 +1,61 @@
+class Solution {
+    private var parent = [Int]()
+    private var weight = [Double]()
+    
+    func calcEquation(
+        _ equations: [[String]], 
+        _ values: [Double], 
+        _ queries: [[String]]
+    ) -> [Double] {
+        let n = equations.count
+        parent = Array(0..<(n * 2))
+        weight = Array(repeating: 1.0, count: n * 2)
+        
+        var map = [String: Int]()
+        var index = 0
+        
+        for i in 0..<n {
+            let a = equations[i][0]
+            let b = equations[i][1]
+            
+            if map[a] == nil {
+                map[a] = index
+                index += 1
+            }
+            if map[b] == nil {
+                map[b] = index
+                index += 1
+            }
+            
+            let pa = find(map[a]!)
+            let pb = find(map[b]!)
+            
+            if pa != pb {
+                parent[pa] = pb
+                weight[pa] = weight[map[b]!] * values[i] / weight[map[a]!]
+            }
+        }
+        
+        var result = [Double]()
+        
+        for query in queries {
+            let (c, d) = (query[0], query[1])
+            if let id1 = map[c], let id2 = map[d], find(id1) == find(id2) {
+                result.append(weight[id1] / weight[id2])
+            } else {
+                result.append(-1.0)
+            }
+        }
+        
+        return result
+    }
+    
+    private func find(_ x: Int) -> Int {
+        if parent[x] != x {
+            let origin = parent[x]
+            parent[x] = find(parent[x])
+            weight[x] *= weight[origin]
+        }
+        return parent[x]
+    }
+}