From a4521de6b7247203200216caeb90a4812f42b41c Mon Sep 17 00:00:00 2001
From: Lanre Adedara <lanre.adedara@shara.co>
Date: Tue, 28 May 2024 07:53:13 +0100
Subject: [PATCH 1/2] Swift implementation for LCOF 49

---
 .../README.md"                                | 86 +++++++++++++++++++
 .../Solution.swift"                           | 81 +++++++++++++++++
 2 files changed, 167 insertions(+)
 create mode 100644 "lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/Solution.swift"

diff --git "a/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md" "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"
index 304d451aaea7f..27673980d97b8 100644
--- "a/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"	
+++ "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"	
@@ -237,6 +237,92 @@ public class Solution {
 }
 ```
 
+#### Swift
+
+```swift
+class Solution {
+    func nthUglyNumber(_ n: Int) -> Int {
+        var vis = Set<Int64>()
+        var pq = PriorityQueue<Int64>()
+        let factors: [Int64] = [2, 3, 5]
+        
+        pq.push(1)
+        vis.insert(1)
+        var ans: Int64 = 0
+        
+        for _ in 0..<n {
+            ans = pq.pop()!
+            for factor in factors {
+                let next = ans * factor
+                if vis.insert(next).inserted {
+                    pq.push(next)
+                }
+            }
+        }
+        
+        return Int(ans)
+    }
+}
+
+struct PriorityQueue<T: Comparable> {
+    private var heap: [T] = []
+    
+    var isEmpty: Bool {
+        return heap.isEmpty
+    }
+    
+    mutating func push(_ element: T) {
+        heap.append(element)
+        heapifyUp(from: heap.count - 1)
+    }
+    
+    mutating func pop() -> T? {
+        guard !heap.isEmpty else {
+            return nil
+        }
+        if heap.count == 1 {
+            return heap.removeLast()
+        }
+        let value = heap[0]
+        heap[0] = heap.removeLast()
+        heapifyDown(from: 0)
+        return value
+    }
+    
+    private mutating func heapifyUp(from index: Int) {
+        var index = index
+        let element = heap[index]
+        while index > 0 {
+            let parentIndex = (index - 1) / 2
+            if element >= heap[parentIndex] {
+                break
+            }
+            heap[index] = heap[parentIndex]
+            index = parentIndex
+        }
+        heap[index] = element
+    }
+    
+    private mutating func heapifyDown(from index: Int) {
+        var index = index
+        let element = heap[index]
+        let count = heap.count
+        while index < count / 2 {
+            var childIndex = index * 2 + 1
+            if childIndex + 1 < count && heap[childIndex + 1] < heap[childIndex] {
+                childIndex += 1
+            }
+            if element <= heap[childIndex] {
+                break
+            }
+            heap[index] = heap[childIndex]
+            index = childIndex
+        }
+        heap[index] = element
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->
diff --git "a/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/Solution.swift" "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/Solution.swift"
new file mode 100644
index 0000000000000..04dfddcd4b3da
--- /dev/null
+++ "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/Solution.swift"	
@@ -0,0 +1,81 @@
+class Solution {
+    func nthUglyNumber(_ n: Int) -> Int {
+        var vis = Set<Int64>()
+        var pq = PriorityQueue<Int64>()
+        let factors: [Int64] = [2, 3, 5]
+        
+        pq.push(1)
+        vis.insert(1)
+        var ans: Int64 = 0
+        
+        for _ in 0..<n {
+            ans = pq.pop()!
+            for factor in factors {
+                let next = ans * factor
+                if vis.insert(next).inserted {
+                    pq.push(next)
+                }
+            }
+        }
+        
+        return Int(ans)
+    }
+}
+
+struct PriorityQueue<T: Comparable> {
+    private var heap: [T] = []
+    
+    var isEmpty: Bool {
+        return heap.isEmpty
+    }
+    
+    mutating func push(_ element: T) {
+        heap.append(element)
+        heapifyUp(from: heap.count - 1)
+    }
+    
+    mutating func pop() -> T? {
+        guard !heap.isEmpty else {
+            return nil
+        }
+        if heap.count == 1 {
+            return heap.removeLast()
+        }
+        let value = heap[0]
+        heap[0] = heap.removeLast()
+        heapifyDown(from: 0)
+        return value
+    }
+    
+    private mutating func heapifyUp(from index: Int) {
+        var index = index
+        let element = heap[index]
+        while index > 0 {
+            let parentIndex = (index - 1) / 2
+            if element >= heap[parentIndex] {
+                break
+            }
+            heap[index] = heap[parentIndex]
+            index = parentIndex
+        }
+        heap[index] = element
+    }
+    
+    private mutating func heapifyDown(from index: Int) {
+        var index = index
+        let element = heap[index]
+        let count = heap.count
+        while index < count / 2 {
+            var childIndex = index * 2 + 1
+            if childIndex + 1 < count && heap[childIndex + 1] < heap[childIndex] {
+                childIndex += 1
+            }
+            if element <= heap[childIndex] {
+                break
+            }
+            heap[index] = heap[childIndex]
+            index = childIndex
+        }
+        heap[index] = element
+    }
+}
\ No newline at end of file

From 4a05bd52be9e46d3bf749b32e34aa84325e099aa Mon Sep 17 00:00:00 2001
From: yanglbme <yanglbme@users.noreply.github.com>
Date: Tue, 28 May 2024 09:34:32 +0000
Subject: [PATCH 2/2] style: format code and docs with prettier

---
 .../README.md"                                   | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git "a/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md" "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"
index 27673980d97b8..89aef3320acbd 100644
--- "a/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"	
+++ "b/lcof/\351\235\242\350\257\225\351\242\23049. \344\270\221\346\225\260/README.md"	
@@ -245,11 +245,11 @@ class Solution {
         var vis = Set<Int64>()
         var pq = PriorityQueue<Int64>()
         let factors: [Int64] = [2, 3, 5]
-        
+
         pq.push(1)
         vis.insert(1)
         var ans: Int64 = 0
-        
+
         for _ in 0..<n {
             ans = pq.pop()!
             for factor in factors {
@@ -259,23 +259,23 @@ class Solution {
                 }
             }
         }
-        
+
         return Int(ans)
     }
 }
 
 struct PriorityQueue<T: Comparable> {
     private var heap: [T] = []
-    
+
     var isEmpty: Bool {
         return heap.isEmpty
     }
-    
+
     mutating func push(_ element: T) {
         heap.append(element)
         heapifyUp(from: heap.count - 1)
     }
-    
+
     mutating func pop() -> T? {
         guard !heap.isEmpty else {
             return nil
@@ -288,7 +288,7 @@ struct PriorityQueue<T: Comparable> {
         heapifyDown(from: 0)
         return value
     }
-    
+
     private mutating func heapifyUp(from index: Int) {
         var index = index
         let element = heap[index]
@@ -302,7 +302,7 @@ struct PriorityQueue<T: Comparable> {
         }
         heap[index] = element
     }
-    
+
     private mutating func heapifyDown(from index: Int) {
         var index = index
         let element = heap[index]