square869120コンテスト5 A問題 Sushi 2

問題へのリンク

C#のソース

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("1 6");
            WillReturn.Add("4");
            //4
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("3 10");
            WillReturn.Add("3 7 2");
            //12
        }
        else if (InputPattern == "Input3") {
            WillReturn.Add("6 15");
            WillReturn.Add("8 6 9 1 2 0");
            //45
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static void Main()
    {
        List<string> InputList = GetInputList();

        int[] wkArr = InputList[0].Split(' ').Select(pX => int.Parse(pX)).ToArray();
        int T = wkArr[1];

        int[] AArr = InputList[1].Split(' ').Select(pX => int.Parse(pX)).ToArray();

        int CurrTime = 0;
        foreach (int EachA in AArr) {
            int Katamuki = T;
            int Seppen = EachA;
            int Uhen = CurrTime;
            int X = Solve(Katamuki, Seppen, Uhen);
            CurrTime = Katamuki * X + Seppen;
        }
        Console.WriteLine(CurrTime);
    }

    // 不等式 SX + T >= U
    // をXについて解く
    static int Solve(int pKatamuki, int pSeppen, int pUhen)
    {
        pUhen -= pSeppen;
        int Answer = pUhen / pKatamuki;
        if (pUhen % pKatamuki > 0) Answer++;
        return Answer;
    }
}

解説

貪欲法で解いてます。