no message

Author: partho-maple

leetcode.com/swift/DS_ALGO_PRAC.playground/Sources/swift/129_Sum_Root_to_Leaf_Numbers.swift

@@ -54,3 +54,32 @@ class Solution {
         return node.left == nil && node.right == nil
     }
 }
+
+
+// Second try
+class Solution {
+    func sumNumbers(_ root: TreeNode?) -> Int {
+        var currentPath = [Int](), currentSum = 0
+        sumNumbersDFSHelper(root, currentPath, &currentSum)
+        return currentSum
+    }
+
+    func sumNumbersDFSHelper(_ root: TreeNode?, _ currentPath: [Int], _ currentSum: inout Int) {
+        guard let root = root else {
+            return
+        }
+
+        if root.left == nil && root.right == nil {
+            let currentPath = currentPath + [root.val]
+            let currentNumStr = currentPath.reduce("") { $0 + String($1) }
+            let currentNum = Int(currentNumStr)
+            currentSum += currentNum!
+        }
+        if let left = root.left {
+            sumNumbersDFSHelper(left, currentPath + [root.val], &currentSum)
+        }
+        if let right = root.right {
+            sumNumbersDFSHelper(right, currentPath + [root.val], &currentSum)
+        }
+    }
+}

leetcode.com/swift/DS_ALGO_PRAC.playground/Sources/swift/253_Meeting_Rooms_II.swift

@@ -46,3 +46,23 @@ class Solution {
         return occupiedRooms.count
     }
 }
+
+
+
+// Improved Code
+class Solution {
+    func minMeetingRooms(_ intervals: [[Int]]) -> Int {
+        guard intervals.count > 1 else {
+            return 1
+        }
+        let sortedInterval = intervals.sorted { $0[0] < $1[0] }
+        var minHeap: Heap<Int> = Heap<Int>(sort: <)
+        for i in 0..<sortedInterval.count {
+            if let peak = minHeap.peek(), peak <= sortedInterval[i][0] {
+                minHeap.remove()
+            }
+            minHeap.insert(sortedInterval[i][1])
+        }
+        return minHeap.count
+    }
+}