From 344d8078de1f83cf524881e4835a856f955ce1c3 Mon Sep 17 00:00:00 2001
From: Lanre Adedara <lanre.adedara@shara.co>
Date: Thu, 6 Jun 2024 06:27:00 +0100
Subject: [PATCH] feat: add swift implementation to lcof2 problem: No.039

---
 .../README.md"                                | 42 +++++++++++++++++++
 .../Solution.swift"                           | 37 ++++++++++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 "lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/Solution.swift"

diff --git "a/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/README.md" "b/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/README.md"
index 0f92c4a6a385f..ed0922fce83b5 100644
--- "a/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/README.md"	
+++ "b/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/README.md"	
@@ -235,6 +235,48 @@ function largestRectangleArea(heights: number[]): number {
 }
 ```
 
+#### Swift
+
+```swift
+class Solution {
+    func largestRectangleArea(_ heights: [Int]) -> Int {
+        let n = heights.count
+        var left = [Int](repeating: -1, count: n)
+        var right = [Int](repeating: n, count: n)
+        var stack = [Int]()
+
+        for i in 0..<n {
+            while !stack.isEmpty && heights[stack.last!] >= heights[i] {
+                stack.removeLast()
+            }
+            if !stack.isEmpty {
+                left[i] = stack.last!
+            }
+            stack.append(i)
+        }
+
+        stack.removeAll()
+
+        for i in stride(from: n - 1, through: 0, by: -1) {
+            while !stack.isEmpty && heights[stack.last!] >= heights[i] {
+                stack.removeLast()
+            }
+            if !stack.isEmpty {
+                right[i] = stack.last!
+            }
+            stack.append(i)
+        }
+
+        var maxArea = 0
+        for i in 0..<n {
+            maxArea = max(maxArea, (right[i] - left[i] - 1) * heights[i])
+        }
+
+        return maxArea
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->
diff --git "a/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/Solution.swift" "b/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/Solution.swift"
new file mode 100644
index 0000000000000..aa1548fc883fb
--- /dev/null
+++ "b/lcof2/\345\211\221\346\214\207 Offer II 039. \347\233\264\346\226\271\345\233\276\346\234\200\345\244\247\347\237\251\345\275\242\351\235\242\347\247\257/Solution.swift"	
@@ -0,0 +1,37 @@
+class Solution {
+    func largestRectangleArea(_ heights: [Int]) -> Int {
+        let n = heights.count
+        var left = [Int](repeating: -1, count: n)
+        var right = [Int](repeating: n, count: n)
+        var stack = [Int]()
+
+        for i in 0..<n {
+            while !stack.isEmpty && heights[stack.last!] >= heights[i] {
+                stack.removeLast()
+            }
+            if !stack.isEmpty {
+                left[i] = stack.last!
+            }
+            stack.append(i)
+        }
+
+        stack.removeAll()
+
+        for i in stride(from: n - 1, through: 0, by: -1) {
+            while !stack.isEmpty && heights[stack.last!] >= heights[i] {
+                stack.removeLast()
+            }
+            if !stack.isEmpty {
+                right[i] = stack.last!
+            }
+            stack.append(i)
+        }
+
+        var maxArea = 0
+        for i in 0..<n {
+            maxArea = max(maxArea, (right[i] - left[i] - 1) * heights[i])
+        }
+
+        return maxArea
+    }
+}
\ No newline at end of file