LCP 24.数字游戏

https://leetcode.cn/problems/5TxKeK/

Author: szwathub

LCP/24 Nums Game/NumsGame.swift

@@ -0,0 +1,55 @@
+//
+//  Copyright © 2024 Zhiwei Sun. All rights reserved.
+//
+//  File name: NumsGame.swift
+//  Author:    Zhiwei Sun @szwathub
+//  E-mail:    [email protected]
+//
+//  Description:
+//      https://leetcode.cn/problems/5TxKeK/
+//  History:
+//      2024/2/1: Created by szwathub on 2024/2/1
+//
+
+import Structure
+
+class NumsGame {
+
+    func numsGame(_ nums: [Int]) -> [Int] {
+        var ans: [Int] = [Int](repeating: 0, count: nums.count)
+
+        let MOD = 1_000_000_007
+
+        var lowerHeap = Heap<Int>(sort: >) // 大根堆, 维护较小的一半
+        var upperHeap = Heap<Int>(sort: <) // 小根堆, 维护较大的一半
+        var lowerSum = 0, upperSum = 0
+
+        for (index, num) in nums.enumerated() {
+            var x = num - index
+            if index % 2 == 0 { // 前缀长度是奇数
+                if let top = lowerHeap.peek(), x < top {
+                    lowerSum -= top - x
+                    lowerHeap.insert(x)
+                    lowerHeap.remove()
+                    x = top
+                }
+                upperSum += x
+                upperHeap.insert(x)
+                ans[index] = (upperSum - (upperHeap.peek() ?? 0) - lowerSum) % MOD
+            } else {
+                if let top = upperHeap.peek(), x > top {
+                    upperSum += x - top
+                    upperHeap.insert(x)
+                    upperHeap.remove()
+                    x = top
+                }
+
+                lowerSum += x
+                lowerHeap.insert(x)
+                ans[index] = (upperSum - lowerSum) % MOD
+            }
+        }
+
+        return ans
+    }
+}

Package.swift

@@ -7,6 +7,8 @@ let package = Package(
     name: "LeetCode",
     products: [
         // Products define the executables and libraries a package produces, and make them visible to other packages.
+        .library(name: "Structure", targets: ["Structure"]),
+        .library(name: "LCP", targets: ["LCP"]),
         .library(name: "LeetCode", targets: ["LeetCode"])
     ],
     dependencies: [
@@ -16,7 +18,11 @@ let package = Package(
     targets: [
         // Targets are the basic building blocks of a package. A target can define a module or a test suite.
         // Targets can depend on other targets in this package, and on products in packages this package depends on.
-        .target(name: "LeetCode", dependencies: [], path: "LeetCode"),
-        .testTarget(name: "LeetCodeTests", dependencies: ["LeetCode"]),
+        .target(name: "Structure", dependencies: [], path: "Structure"),
+        .target(name: "LCP", dependencies: ["Structure"], path: "LCP"),
+        .target(name: "LeetCode", dependencies: ["Structure"], path: "LeetCode"),
+        .testTarget(name: "LCPTests", dependencies: ["LCP", "Structure"]),
+        .testTarget(name: "LeetCodeTests", dependencies: ["LeetCode", "Structure"]),
+        .testTarget(name: "StructureTests", dependencies: ["Structure"])
     ]
 )

Tests/LCPTests/24 Nums Game/NumsGameSpec.swift

@@ -0,0 +1,21 @@
+import XCTest
+@testable import LCP
+
+final class NumsGameSpec: XCTestCase {
+
+    fileprivate let questions: [(([Int]), [Int])] = [
+        (([3, 4, 5, 1, 6, 7]), [0, 0, 0, 5, 6, 7]),
+        (([1, 2, 3, 4, 5]), [0, 0, 0, 0, 0]),
+        (([1, 1, 1, 2, 3, 4]), [0, 1, 2, 3, 3, 3])
+    ]
+
+    func testNumsGame() {
+        let solution = NumsGame()
+        for ((nums), answer) in questions {
+            XCTAssertEqual(
+                solution.numsGame(nums),
+                answer
+            )
+        }
+    }
+}