feat: add swift implementation to lcp problem: No.11 (doocs#3747)

Author: klever34

lcp/LCP 11. 期望个数统计/README.md

@@ -125,6 +125,17 @@ function expectNumber(scores: number[]): number {
 }
 ```
 
+#### Swift
+
+```swift
+class Solution {
+    func expectNumber(_ scores: [Int]) -> Int {
+        let uniqueScores = Set(scores)
+        return uniqueScores.count
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

lcp/LCP 11. 期望个数统计/Solution.swift

@@ -0,0 +1,6 @@
+class Solution {
+    func expectNumber(_ scores: [Int]) -> Int {
+        let uniqueScores = Set(scores)
+        return uniqueScores.count
+    }
+}