From e2103b400f5e17ed5f5904a737f0dea3d8f29c9d Mon Sep 17 00:00:00 2001
From: Lanre Adedara <lanre.adedara@shara.co>
Date: Sun, 19 Jan 2025 15:29:51 +0100
Subject: [PATCH] feat: add swift implementation to lcp problem: No.62

---
 .../README.md"                                | 35 +++++++++++++++++++
 .../Solution.swift"                           | 30 ++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 "lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/Solution.swift"

diff --git "a/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/README.md" "b/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/README.md"
index 348f106b5e995..690d01b9e1c20 100644
--- "a/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/README.md"	
+++ "b/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/README.md"	
@@ -205,6 +205,41 @@ function transportationHub(path: number[][]): number {
 }
 ```
 
+#### Swift
+
+```swift
+class Solution {
+    func transportationHub(_ path: [[Int]]) -> Int {
+        var inDegree = [Int: Int]()
+        var outDegree = [Int: Int]()
+        var nodeSet = Set<Int>()
+        var visitedEdges = Set<String>()
+
+        for p in path {
+            let a = p[0]
+            let b = p[1]
+            let edgeKey = "\(a)-\(b)"
+
+            if !visitedEdges.contains(edgeKey) {
+                visitedEdges.insert(edgeKey)
+                nodeSet.insert(a)
+                nodeSet.insert(b)
+                inDegree[b, default: 0] += 1
+                outDegree[a, default: 0] += 1
+            }
+        }
+
+        for node in nodeSet {
+            if inDegree[node, default: 0] == nodeSet.count - 1 && outDegree[node, default: 0] == 0 {
+                return node
+            }
+        }
+
+        return -1
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->
diff --git "a/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/Solution.swift" "b/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/Solution.swift"
new file mode 100644
index 0000000000000..dca4332f4a733
--- /dev/null
+++ "b/lcp/LCP 62. \344\272\244\351\200\232\346\236\242\347\272\275/Solution.swift"	
@@ -0,0 +1,30 @@
+class Solution {
+    func transportationHub(_ path: [[Int]]) -> Int {
+        var inDegree = [Int: Int]()
+        var outDegree = [Int: Int]()
+        var nodeSet = Set<Int>()
+        var visitedEdges = Set<String>()
+
+        for p in path {
+            let a = p[0]
+            let b = p[1]
+            let edgeKey = "\(a)-\(b)"
+
+            if !visitedEdges.contains(edgeKey) {
+                visitedEdges.insert(edgeKey)
+                nodeSet.insert(a)
+                nodeSet.insert(b)
+                inDegree[b, default: 0] += 1
+                outDegree[a, default: 0] += 1
+            }
+        }
+
+        for node in nodeSet {
+            if inDegree[node, default: 0] == nodeSet.count - 1 && outDegree[node, default: 0] == 0 {
+                return node
+            }
+        }
+
+        return -1
+    }
+}
\ No newline at end of file