feat: add swift implementation to lcci problem: No.10.05 (#2714)

Author: klever34

lcci/10.05.Sparse Array Search/README.md

@@ -144,6 +144,29 @@ function findString(words: string[], s: string): number {
 }
 ```
 
+```swift
+class Solution {
+    func findString(_ words: [String], _ s: String) -> Int {
+        return dfs(words, s, 0, words.count - 1)
+    }
+
+    private func dfs(_ words: [String], _ s: String, _ i: Int, _ j: Int) -> Int {
+        if i > j {
+            return -1
+        }
+        let mid = (i + j) >> 1
+        let left = dfs(words, s, i, mid - 1)
+        if left != -1 {
+            return left
+        }
+        if words[mid] == s {
+            return mid
+        }
+        return dfs(words, s, mid + 1, j)
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/10.05.Sparse Array Search/README_EN.md

@@ -150,6 +150,29 @@ function findString(words: string[], s: string): number {
 }
 ```
 
+```swift
+class Solution {
+    func findString(_ words: [String], _ s: String) -> Int {
+        return dfs(words, s, 0, words.count - 1)
+    }
+
+    private func dfs(_ words: [String], _ s: String, _ i: Int, _ j: Int) -> Int {
+        if i > j {
+            return -1
+        }
+        let mid = (i + j) >> 1
+        let left = dfs(words, s, i, mid - 1)
+        if left != -1 {
+            return left
+        }
+        if words[mid] == s {
+            return mid
+        }
+        return dfs(words, s, mid + 1, j)
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/10.05.Sparse Array Search/Solution.swift

@@ -0,0 +1,20 @@
+class Solution {
+    func findString(_ words: [String], _ s: String) -> Int {
+        return dfs(words, s, 0, words.count - 1)
+    }
+
+    private func dfs(_ words: [String], _ s: String, _ i: Int, _ j: Int) -> Int {
+        if i > j {
+            return -1
+        }
+        let mid = (i + j) >> 1
+        let left = dfs(words, s, i, mid - 1)
+        if left != -1 {
+            return left
+        }
+        if words[mid] == s {
+            return mid
+        }
+        return dfs(words, s, mid + 1, j)
+    }
+}