feat: Add solution for LeetCode problem 213

Author: WhiteHyun

house-robber-ii/WhiteHyun.swift

@@ -0,0 +1,30 @@
+//  
+//  213. House Robber II
+//  https://leetcode.com/problems/house-robber-ii/description/
+//  Dale-Study
+//  
+//  Created by WhiteHyun on 2024/07/06.
+//  
+
+class Solution {
+  func rob(_ nums: [Int]) -> Int {
+    if nums.count < 3 { return nums.max()! }
+    var current = 0
+    var previous = 0
+    
+    // 첫 번째 집을 턴 경우
+    for element in nums.dropLast() {
+      (previous, current) = (current, max(element + previous, current))
+    }
+
+    var current2 = 0
+    var previous2 = 0
+
+    // 첫 번째 집을 털지 않은 경우
+    for element in nums.dropFirst() {
+      (previous2, current2) = (current2, max(element + previous2, current2))
+    }
+
+    return max(current, previous, current2, previous2)
+  }
+}