結果

問題 No.834 Random Walk Trip
ユーザー EmKjpEmKjp
提出日時 2019-05-24 23:55:58
言語 C#(csc)
(csc 3.9.0)
結果
WA  
実行時間 -
コード長 5,017 bytes
コンパイル時間 1,582 ms
コンパイル使用メモリ 114,288 KB
実行使用メモリ 48,736 KB
最終ジャッジ日時 2024-09-17 12:52:03
合計ジャッジ時間 3,179 ms
ジャッジサーバーID
(参考情報)
judge6 / judge2
このコードへのチャレンジ
(要ログイン)

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 21 ms
23,856 KB
testcase_01 AC 21 ms
25,936 KB
testcase_02 AC 23 ms
26,016 KB
testcase_03 AC 21 ms
23,896 KB
testcase_04 AC 22 ms
23,996 KB
testcase_05 AC 22 ms
26,160 KB
testcase_06 AC 21 ms
23,864 KB
testcase_07 AC 22 ms
26,036 KB
testcase_08 AC 20 ms
22,072 KB
testcase_09 WA -
testcase_10 AC 20 ms
23,772 KB
testcase_11 AC 20 ms
25,936 KB
testcase_12 AC 21 ms
23,900 KB
testcase_13 AC 21 ms
23,900 KB
testcase_14 AC 20 ms
21,940 KB
testcase_15 AC 21 ms
21,940 KB
testcase_16 AC 22 ms
25,956 KB
testcase_17 AC 25 ms
24,880 KB
testcase_18 AC 33 ms
27,364 KB
testcase_19 AC 95 ms
46,576 KB
testcase_20 AC 35 ms
27,160 KB
testcase_21 AC 89 ms
46,252 KB
testcase_22 AC 23 ms
26,040 KB
testcase_23 AC 93 ms
41,600 KB
testcase_24 AC 26 ms
24,416 KB
testcase_25 AC 117 ms
48,736 KB
権限があれば一括ダウンロードができます
コンパイルメッセージ
Microsoft (R) Visual C# Compiler version 3.9.0-6.21124.20 (db94f4cc)
Copyright (C) Microsoft Corporation. All rights reserved.

ソースコード

diff #

using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;

partial class Solver
{
    public void Run()
    {
        var N = ni();
        var M = ni();

        int mod = 1000000007;
        long ans = 0;
        if (N == 1) ans = 1;
        else
        {
            var C = new Binomial(M + 1, mod);
            var pattern = new Func<int, long>(x =>
            {
                if ((M + x) % 2 == 1) return 0;
                var a = (M + x) / 2;
                return C[M, a];
            }
            );
            for (int i = 0; i <= M; i += 2 * N)
            {
                var a = i;
                var b = i - 1;

                if (a >= 0 && a <= M) ans += pattern(a);
                if (b >= 0 && b <= M) ans += pattern(b);
                ans %= mod;
            }
            for (int i = 0; i >= -M; i -= 2 * N)
            {
                var a = i;
                var b = i - 1;

                if (a < 0 && -M <= a) ans += pattern(-a);
                if (b < 0 && -M <= b) ans += pattern(-b);
                ans %= mod;
            }
        }
        cout.WriteLine(ans);

    }
}

public class Binomial
{
    private readonly long[] factorial;
    private readonly long[] inverseFactorial;
    private readonly long[] inverse;
    private readonly int mod;

    public Binomial(int size, int primeMod)
    {
        size++;
        this.factorial = new long[size];
        this.inverseFactorial = new long[size];
        this.inverse = new long[size];
        this.mod = primeMod;
        Setup(size);
    }

    private void Setup(int size)
    {
        factorial[0] = factorial[1] = 1;
        inverseFactorial[0] = inverseFactorial[1] = 1;
        inverse[1] = 1;
        for (int i = 2; i < size; i++)
        {
            factorial[i] = factorial[i - 1] * i % mod;
            inverse[i] = (mod - (mod / i) * inverse[mod % i] % mod);
            inverseFactorial[i] = inverseFactorial[i - 1] * inverse[i] % mod;
        }
    }

    private long Get(int s, int t)
    {
        if (s < 0 || t < 0 || s < t) return 0;
        if (t == 0 || s == t) return 1;
        if (s >= mod) return Get(s % mod, t % mod) * Get(s / mod, t / mod) % mod; // Lucas' theorem
        return factorial[s] * inverseFactorial[t] % mod * inverseFactorial[s - t] % mod;
    }

    public long this[int s, int t]
    {
        get
        {
            return Get(s, t);
        }
    }

}

// PREWRITEN CODE BEGINS FROM HERE
partial class Solver : Scanner
{
    public static void Main(string[] args)
    {
        new Solver(Console.In, Console.Out).Run();
    }

    TextReader cin;
    TextWriter cout;

    public Solver(TextReader reader, TextWriter writer)
        : base(reader)
    {
        this.cin = reader;
        this.cout = writer;
    }
    public Solver(string input, TextWriter writer)
        : this(new StringReader(input), writer)
    {
    }

    public int ni() { return NextInt(); }
    public int[] ni(int n) { return NextIntArray(n); }
    public long nl() { return NextLong(); }
    public long[] nl(int n) { return NextLongArray(n); }
    public double nd() { return NextDouble(); }
    public string ns() { return Next(); }
}

public class Scanner
{
    private TextReader Reader;
    private Queue<String> TokenQueue = new Queue<string>();
    private CultureInfo ci = CultureInfo.InvariantCulture;

    public Scanner()
        : this(Console.In)
    {
    }

    public Scanner(TextReader reader)
    {
        this.Reader = reader;
    }

    public int NextInt() { return Int32.Parse(Next(), ci); }
    public long NextLong() { return Int64.Parse(Next(), ci); }
    public double NextDouble() { return double.Parse(Next(), ci); }
    public string[] NextArray(int size)
    {
        var array = new string[size];
        for (int i = 0; i < size; i++) array[i] = Next();
        return array;
    }
    public int[] NextIntArray(int size)
    {
        var array = new int[size];
        for (int i = 0; i < size; i++) array[i] = NextInt();
        return array;
    }

    public long[] NextLongArray(int size)
    {
        var array = new long[size];
        for (int i = 0; i < size; i++) array[i] = NextLong();
        return array;
    }

    public String Next()
    {
        if (TokenQueue.Count == 0)
        {
            if (!StockTokens()) throw new InvalidOperationException();
        }
        return TokenQueue.Dequeue();
    }

    public bool HasNext()
    {
        if (TokenQueue.Count > 0)
            return true;
        return StockTokens();
    }

    private bool StockTokens()
    {
        while (true)
        {
            var line = Reader.ReadLine();
            if (line == null) return false;
            var tokens = line.Trim().Split(" ".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
            if (tokens.Length == 0) continue;
            foreach (var token in tokens)
                TokenQueue.Enqueue(token);
            return true;
        }
    }
}
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