feat: add swift implementation to lcci problem: No.16.04

lcci/16.04.Tic-Tac-Toe/README.md

@@ -230,6 +230,41 @@ function tictactoe(board: string[]): string {
     return hasEmptyGrid ? 'Pending' : 'Draw';
 }
 ```
+```swift
+class Solution {
+    func tictactoe(_ board: [String]) -> String {
+        let n = board.count
+        var rows = Array(repeating: 0, count: n)
+        var cols = Array(repeating: 0, count: n)
+        var diagonal = 0, antiDiagonal = 0
+        var hasEmptyGrid = false
+
+        for i in 0..<n {
+            for j in 0..<n {
+                let c = Array(board[i])[j]
+                if c == " " {
+                    hasEmptyGrid = true
+                    continue
+                }
+                let value = c == "X" ? 1 : -1
+                rows[i] += value
+                cols[j] += value
+                if i == j {
+                    diagonal += value
+                }
+                if i + j == n - 1 {
+                    antiDiagonal += value
+                }
+                if abs(rows[i]) == n || abs(cols[j]) == n || abs(diagonal) == n || abs(antiDiagonal) == n {
+                    return String(c)
+                }
+            }
+        }
+
+        return hasEmptyGrid ? "Pending" : "Draw"
+    }
+}
+```
 
 <!-- tabs:end -->
 

lcci/16.04.Tic-Tac-Toe/README_EN.md

@@ -243,6 +243,42 @@ function tictactoe(board: string[]): string {
 }
 ```
 
+```swift
+class Solution {
+    func tictactoe(_ board: [String]) -> String {
+        let n = board.count
+        var rows = Array(repeating: 0, count: n)
+        var cols = Array(repeating: 0, count: n)
+        var diagonal = 0, antiDiagonal = 0
+        var hasEmptyGrid = false
+
+        for i in 0..<n {
+            for j in 0..<n {
+                let c = Array(board[i])[j]
+                if c == " " {
+                    hasEmptyGrid = true
+                    continue
+                }
+                let value = c == "X" ? 1 : -1
+                rows[i] += value
+                cols[j] += value
+                if i == j {
+                    diagonal += value
+                }
+                if i + j == n - 1 {
+                    antiDiagonal += value
+                }
+                if abs(rows[i]) == n || abs(cols[j]) == n || abs(diagonal) == n || abs(antiDiagonal) == n {
+                    return String(c)
+                }
+            }
+        }
+
+        return hasEmptyGrid ? "Pending" : "Draw"
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/16.04.Tic-Tac-Toe/Solution.swift

@@ -0,0 +1,33 @@
+class Solution {
+    func tictactoe(_ board: [String]) -> String {
+        let n = board.count
+        var rows = Array(repeating: 0, count: n)
+        var cols = Array(repeating: 0, count: n)
+        var diagonal = 0, antiDiagonal = 0
+        var hasEmptyGrid = false
+
+        for i in 0..<n {
+            for j in 0..<n {
+                let c = Array(board[i])[j]
+                if c == " " {
+                    hasEmptyGrid = true
+                    continue
+                }
+                let value = c == "X" ? 1 : -1
+                rows[i] += value
+                cols[j] += value
+                if i == j {
+                    diagonal += value
+                }
+                if i + j == n - 1 {
+                    antiDiagonal += value
+                }
+                if abs(rows[i]) == n || abs(cols[j]) == n || abs(diagonal) == n || abs(antiDiagonal) == n {
+                    return String(c)
+                }
+            }
+        }
+
+        return hasEmptyGrid ? "Pending" : "Draw"
+    }
+}