feat: add swift implementation to lcci problem: No.08.10 (doocs#2696)

Author: klever34

lcci/08.10.Color Fill/README.md

@@ -192,6 +192,33 @@ impl Solution {
 }
 ```
 
+```swift
+class Solution {
+    private var dirs = [-1, 0, 1, 0, -1]
+    private var image: [[Int]] = []
+    private var nc: Int = 0
+    private var oc: Int = 0
+
+    func floodFill(_ image: inout [[Int]], _ sr: Int, _ sc: Int, _ newColor: Int) -> [[Int]] {
+        self.nc = newColor
+        self.oc = image[sr][sc]
+        self.image = image
+        dfs(sr, sc)
+        return self.image
+    }
+
+    private func dfs(_ i: Int, _ j: Int) {
+        if i < 0 || i >= image.count || j < 0 || j >= image[0].count || image[i][j] != oc || image[i][j] == nc {
+            return
+        }
+        image[i][j] = nc
+        for k in 0..<4 {
+            dfs(i + dirs[k], j + dirs[k + 1])
+        }
+    }
+}
+```
+
 <!-- tabs:end -->
 
 ### 方法二：BFS

lcci/08.10.Color Fill/README_EN.md

@@ -199,6 +199,33 @@ impl Solution {
 }
 ```
 
+```swift
+class Solution {
+    private var dirs = [-1, 0, 1, 0, -1]
+    private var image: [[Int]] = []
+    private var nc: Int = 0
+    private var oc: Int = 0
+
+    func floodFill(_ image: inout [[Int]], _ sr: Int, _ sc: Int, _ newColor: Int) -> [[Int]] {
+        self.nc = newColor
+        self.oc = image[sr][sc]
+        self.image = image
+        dfs(sr, sc)
+        return self.image
+    }
+
+    private func dfs(_ i: Int, _ j: Int) {
+        if i < 0 || i >= image.count || j < 0 || j >= image[0].count || image[i][j] != oc || image[i][j] == nc {
+            return
+        }
+        image[i][j] = nc
+        for k in 0..<4 {
+            dfs(i + dirs[k], j + dirs[k + 1])
+        }
+    }
+}
+```
+
 <!-- tabs:end -->
 
 ### Solution 2: BFS

lcci/08.10.Color Fill/Solution.swift

@@ -0,0 +1,24 @@
+class Solution {
+    private var dirs = [-1, 0, 1, 0, -1]
+    private var image: [[Int]] = []
+    private var nc: Int = 0
+    private var oc: Int = 0
+
+    func floodFill(_ image: inout [[Int]], _ sr: Int, _ sc: Int, _ newColor: Int) -> [[Int]] {
+        self.nc = newColor
+        self.oc = image[sr][sc]
+        self.image = image
+        dfs(sr, sc)
+        return self.image
+    }
+
+    private func dfs(_ i: Int, _ j: Int) {
+        if i < 0 || i >= image.count || j < 0 || j >= image[0].count || image[i][j] != oc || image[i][j] == nc {
+            return
+        }
+        image[i][j] = nc
+        for k in 0..<4 {
+            dfs(i + dirs[k], j + dirs[k + 1])
+        }
+    }
+}