DSL_3_A: The Smallest Window I

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("6 5");
            WillReturn.Add("1 2 3 4 5 6");
            WillReturn.Add("6 9 12 21 15");
            //9
            //12
            //15
            //21
            //18
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("6 5");
            WillReturn.Add("5 10 8 8 8 1");
            WillReturn.Add("27 1 30 18 3");
            //16
            //1
            //16
            //12
            //1
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

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

        long[] AArr = InputList[1].Split(' ').Select(pX => long.Parse(pX)).ToArray();
        long[] QArr = InputList[2].Split(' ').Select(pX => long.Parse(pX)).ToArray();

        foreach (long EachQ in QArr) {
            long Answer = 0;

            long CurrSum = AArr[0];
            long R = 0;
            long UB = AArr.GetUpperBound(0);
            for (long L = 0; L <= UB; L++) {
                if (R < L) {
                    R = L;
                    CurrSum = AArr[L];
                }

                while (R + 1 <= UB && CurrSum + AArr[R + 1] <= EachQ) {
                    CurrSum += AArr[R + 1];
                    R++;
                }
                if (L == R) {
                    if (CurrSum <= EachQ) {
                        Answer++;
                    }
                }
                else {
                    Answer += R - L + 1;
                }

                CurrSum -= AArr[L];
            }
            Console.WriteLine(Answer);
        }
    }
}

解説

二分探索だとTLEしたので、
尺取法を使ってます。