Create SockMerchant.swift

Author: devssun

Algorithm/hackerRank/SockMerchant.swift

@@ -0,0 +1,29 @@
+// https://www.hackerrank.com/challenges/sock-merchant/problem
+import Foundation
+
+// Complete the sockMerchant function below.
+// 양말 짝 맞추기
+// 10 20 20 10 10 30 50 10 20 일 때 짝이 되는 갯수는 3 (10, 10) (10, 10) (20, 20)
+func sockMerchant(n: Int, ar: [Int]) -> Int {
+    if n >= 1 && n <= 100 { "invalid" }
+    var counts = [Int]()
+    var result: Int = 0
+    
+    let uniqueArray = Array(Set(ar))
+    
+    for i in 0..<uniqueArray.count {
+        var num = 0
+        for j in 0..<ar.count {
+            if uniqueArray[i] == ar[j] {
+                num += 1
+            }
+        }
+        counts.append(num)
+    }
+    
+    for i in 0..<counts.count {
+        result += counts[i] / 2
+    }
+    
+    return result
+}