feat: add swift implementation to lcci problem: No.17.13 (doocs#2784)

Author: klever34

lcci/17.13.Re-Space/README.md

@@ -108,6 +108,62 @@ func respace(dictionary []string, sentence string) int {
 }
 ```
 
+```swift
+class TrieNode {
+    var children: [TrieNode?] = Array(repeating: nil, count: 26)
+    var isEndOfWord = false
+}
+
+class Trie {
+    private let root = TrieNode()
+
+    func insert(_ word: String) {
+        var node = root
+        for char in word {
+            let index = Int(char.asciiValue! - Character("a").asciiValue!)
+            if node.children[index] == nil {
+                node.children[index] = TrieNode()
+            }
+            node = node.children[index]!
+        }
+        node.isEndOfWord = true
+    }
+
+    func search(_ sentence: Array<Character>, start: Int, end: Int) -> Bool {
+        var node = root
+        for i in start...end {
+            let index = Int(sentence[i].asciiValue! - Character("a").asciiValue!)
+            guard let nextNode = node.children[index] else {
+                return false
+            }
+            node = nextNode
+        }
+        return node.isEndOfWord
+    }
+}
+
+class Solution {
+    func respace(_ dictionary: [String], _ sentence: String) -> Int {
+        let n = sentence.count
+        guard n > 0 else { return 0 }
+        let trie = Trie()
+        dictionary.forEach { trie.insert($0) }
+        let chars = Array(sentence)
+        var dp = Array(repeating: Int.max, count: n + 1)
+        dp[0] = 0
+        for i in 1...n {
+            dp[i] = dp[i - 1] + 1
+            for j in 0..<i {
+                if trie.search(chars, start: j, end: i - 1) {
+                    dp[i] = min(dp[i], dp[j])
+                }
+            }
+        }
+        return dp[n]
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/17.13.Re-Space/README_EN.md

@@ -113,6 +113,62 @@ func respace(dictionary []string, sentence string) int {
 }
 ```
 
+```swift
+class TrieNode {
+    var children: [TrieNode?] = Array(repeating: nil, count: 26)
+    var isEndOfWord = false
+}
+
+class Trie {
+    private let root = TrieNode()
+
+    func insert(_ word: String) {
+        var node = root
+        for char in word {
+            let index = Int(char.asciiValue! - Character("a").asciiValue!)
+            if node.children[index] == nil {
+                node.children[index] = TrieNode()
+            }
+            node = node.children[index]!
+        }
+        node.isEndOfWord = true
+    }
+
+    func search(_ sentence: Array<Character>, start: Int, end: Int) -> Bool {
+        var node = root
+        for i in start...end {
+            let index = Int(sentence[i].asciiValue! - Character("a").asciiValue!)
+            guard let nextNode = node.children[index] else {
+                return false
+            }
+            node = nextNode
+        }
+        return node.isEndOfWord
+    }
+}
+
+class Solution {
+    func respace(_ dictionary: [String], _ sentence: String) -> Int {
+        let n = sentence.count
+        guard n > 0 else { return 0 }
+        let trie = Trie()
+        dictionary.forEach { trie.insert($0) }
+        let chars = Array(sentence)
+        var dp = Array(repeating: Int.max, count: n + 1)
+        dp[0] = 0
+        for i in 1...n {
+            dp[i] = dp[i - 1] + 1
+            for j in 0..<i {
+                if trie.search(chars, start: j, end: i - 1) {
+                    dp[i] = min(dp[i], dp[j])
+                }
+            }
+        }
+        return dp[n]
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/17.13.Re-Space/Solution.swift

@@ -0,0 +1,53 @@
+class TrieNode {
+    var children: [TrieNode?] = Array(repeating: nil, count: 26)
+    var isEndOfWord = false
+}
+
+class Trie {
+    private let root = TrieNode()
+
+    func insert(_ word: String) {
+        var node = root
+        for char in word {
+            let index = Int(char.asciiValue! - Character("a").asciiValue!)
+            if node.children[index] == nil {
+                node.children[index] = TrieNode()
+            }
+            node = node.children[index]!
+        }
+        node.isEndOfWord = true
+    }
+
+    func search(_ sentence: Array<Character>, start: Int, end: Int) -> Bool {
+        var node = root
+        for i in start...end {
+            let index = Int(sentence[i].asciiValue! - Character("a").asciiValue!)
+            guard let nextNode = node.children[index] else {
+                return false
+            }
+            node = nextNode
+        }
+        return node.isEndOfWord
+    }
+}
+
+class Solution {
+    func respace(_ dictionary: [String], _ sentence: String) -> Int {
+        let n = sentence.count
+        guard n > 0 else { return 0 }
+        let trie = Trie()
+        dictionary.forEach { trie.insert($0) }
+        let chars = Array(sentence)
+        var dp = Array(repeating: Int.max, count: n + 1)
+        dp[0] = 0
+        for i in 1...n {
+            dp[i] = dp[i - 1] + 1
+            for j in 0..<i {
+                if trie.search(chars, start: j, end: i - 1) {
+                    dp[i] = min(dp[i], dp[j])
+                }
+            }
+        }
+        return dp[n]
+    }
+}