feat: add swift implementation to lcci problem: No.16.20 (doocs#2763)

Author: klever34

lcci/16.20.T9/README.md

@@ -154,6 +154,34 @@ function getValidT9Words(num: string, words: string[]): string[] {
 }
 ```
 
+```swift
+class Solution {
+    func getValidT9Words(_ num: String, _ words: [String]) -> [String] {
+        let s = "22233344455566677778889999"
+        var d = Array(repeating: 0, count: 26)
+        for i in 0..<26 {
+            d[i] = Int(s[s.index(s.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+        }
+        var ans: [String] = []
+        let n = num.count
+        for w in words {
+            var ok = true
+            for i in 0..<n {
+                let numChar = Int(num[num.index(num.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+                if d[Int(w[w.index(w.startIndex, offsetBy: i)].asciiValue! - Character("a").asciiValue!)] != numChar {
+                    ok = false
+                    break
+                }
+            }
+            if ok {
+                ans.append(w)
+            }
+        }
+        return ans
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/16.20.T9/README_EN.md

@@ -160,6 +160,34 @@ function getValidT9Words(num: string, words: string[]): string[] {
 }
 ```
 
+```swift
+class Solution {
+    func getValidT9Words(_ num: String, _ words: [String]) -> [String] {
+        let s = "22233344455566677778889999"
+        var d = Array(repeating: 0, count: 26)
+        for i in 0..<26 {
+            d[i] = Int(s[s.index(s.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+        }
+        var ans: [String] = []
+        let n = num.count
+        for w in words {
+            var ok = true
+            for i in 0..<n {
+                let numChar = Int(num[num.index(num.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+                if d[Int(w[w.index(w.startIndex, offsetBy: i)].asciiValue! - Character("a").asciiValue!)] != numChar {
+                    ok = false
+                    break
+                }
+            }
+            if ok {
+                ans.append(w)
+            }
+        }
+        return ans
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/16.20.T9/Solution.swift

@@ -0,0 +1,25 @@
+class Solution {
+    func getValidT9Words(_ num: String, _ words: [String]) -> [String] {
+        let s = "22233344455566677778889999"
+        var d = Array(repeating: 0, count: 26)
+        for i in 0..<26 {
+            d[i] = Int(s[s.index(s.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+        }
+        var ans: [String] = []
+        let n = num.count
+        for w in words {
+            var ok = true
+            for i in 0..<n {
+                let numChar = Int(num[num.index(num.startIndex, offsetBy: i)].asciiValue! - Character("0").asciiValue!)
+                if d[Int(w[w.index(w.startIndex, offsetBy: i)].asciiValue! - Character("a").asciiValue!)] != numChar {
+                    ok = false
+                    break
+                }
+            }
+            if ok {
+                ans.append(w)
+            }
+        }
+        return ans
+    }
+}