#431281 (C#(csc)) No.992 最長増加部分列の数え上げ

• 問題: No.992 最長増加部分列の数え上げ
• ユーザー: EmKjp
• 提出日時: 2020-02-18 01:35:58
• 言語: C#(csc) (csc 3.9.0)
• 結果: AC
• 実行時間: 768 ms / 2,000 ms
• コード長: 9,410 bytes
• コンパイル時間: 1,677 ms
• コンパイル使用メモリ: 120,756 KB
• 実行使用メモリ: 56,772 KB
• 最終ジャッジ日時: 2024-10-06 15:21:23
• 合計ジャッジ時間: 26,214 ms
• ジャッジサーバーID （参考情報）: judge3 / judge2

ファイルパターン	結果
sample	AC * 3
other	AC * 42

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

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

using E = System.Linq.Enumerable;
using System.Threading;


internal partial class Solver {
    struct Data {
        public int MaxValue;
        public long Pattern;
    }

    public void Run() {
        var n = ni();
        var a = ni(n);
        var d = IndexDictionaryFactory.Create(a);
        for (int i = 0; i < n; i++) {
            a[i] = d.IndexOf(a[i]) + 1;
        }
        int mod = 1000000000 + 7;
        var tree = new AnonymousSegmentTree<Data>((d1, d2) => {
            if (d1.MaxValue == d2.MaxValue) return new Data { MaxValue = d1.MaxValue, Pattern = (d1.Pattern + d2.Pattern) % mod };
            if (d1.MaxValue < d2.MaxValue) return d2;
            return d1;
        });

        tree.Build(n + 1, i => new Data());

        foreach (var x in a) {

            var max = tree.Query(0, x);

            var current = tree.Query(x, x + 1);

            if (max.Pattern == 0) {
                max.Pattern = 1;
                max.MaxValue = 1;
            } else {
                max.MaxValue++;
            }

            if (current.MaxValue == max.MaxValue) {
                tree.Update(x, new Data { MaxValue = current.MaxValue, Pattern = (current.Pattern + max.Pattern) % mod });
            } else {
                tree.Update(x, max);
            }
        }

        var ans = tree.Query(0, n + 1);

        cout.WriteLine(ans.Pattern);
    }
}

public class IndexDictionary<T> {
    private readonly Dictionary<T, int> _toIndex;
    private readonly T[] _array;

    public IndexDictionary(IEnumerable<T> source) : this(source, Comparer<T>.Default) { }

    public IndexDictionary(IEnumerable<T> source, IComparer<T> comparer) {
        _array = source.Distinct().ToArray();
        Array.Sort(_array, comparer);
        _toIndex = new Dictionary<T, int>(_array.Length);
        int index = -1;
        foreach (var x in _array) {
            _toIndex[x] = ++index;
        }
    }

    public int Count { get { return _array.Length; } }

    public T this[int index] { get { return _array[index]; } }

    public int IndexOf(T value) { return _toIndex[value]; }
}

public class IndexDictionaryFactory {
    public static IndexDictionary<T> Create<T>(IEnumerable<T> source) {
        return new IndexDictionary<T>(source);
    }
}
public abstract class SegmentTree<TMonoid> where TMonoid : struct {
    protected int N { get; private set; }
    protected TMonoid?[] node;
    protected static int Left(int p) { return p * 2 + 1; }
    protected static int Right(int p) { return p * 2 + 2; }

    public SegmentTree() { }

    public void Build(IList<TMonoid> array) {
        Build(array.Count, i => array[i]);
    }

    public virtual void Build(int _n, Func<int, TMonoid> create) {
        N = 1;
        while (N < _n) {
            N *= 2;
        }

        node = new TMonoid?[2 * N];

        for (int i = 0; i < _n; i++) {
            node[i + N - 1] = create(i);
        }

        for (int i = N - 2; i >= 0; i--) {
            node[i] = Merge(node[Left(i)], node[Right(i)]);
        }
    }

    protected TMonoid? Merge(TMonoid? left, TMonoid? right) {
        if (left != null && right != null) {
            return Merge(left.Value, right.Value);
        }

        if (left == null) {
            return right;
        }

        if (right == null) {
            return left;
        }

        return null;
    }

    protected abstract TMonoid Merge(TMonoid left, TMonoid right);

    public void Update(int index, TMonoid val) {
        int p = index + N - 1;
        node[p] = val;
        while (p > 0) {
            p = (p - 1) / 2;
            node[p] = Merge(node[Left(p)], node[Right(p)]);
        }
    }

    protected virtual TMonoid? Query(int begin, int end, int k, int l, int r) {
        if (r <= begin || end <= l) {
            return null;
        }

        if (begin <= l && r <= end) {
            return node[k];
        }

        int mid = (l + r) / 2;
        return Merge(
            Query(begin, end, Left(k), l, mid),
            Query(begin, end, Right(k), mid, r)
        );
    }

    public TMonoid Query(int begin, int end) {
        return Query(begin, end, 0, 0, N).Value;
    }
};

public class AnonymousSegmentTree<TNodeValue> : SegmentTree<TNodeValue> where TNodeValue : struct {
    private readonly Func<TNodeValue, TNodeValue, TNodeValue> _mergeMethod;

    public AnonymousSegmentTree(Func<TNodeValue, TNodeValue, TNodeValue> merge) {
        _mergeMethod = merge;
    }

    protected override TNodeValue Merge(TNodeValue left, TNodeValue right) {
        return _mergeMethod(left, right);
    }
}
// PREWRITEN CODE BEGINS FROM HERE
internal partial class Solver : Scanner {
    public static void Main(string[] args) {
#if LOCAL
        byte[] inputBuffer = new byte[1000000];
        var inputStream = Console.OpenStandardInput(inputBuffer.Length);
        using (var reader = new StreamReader(inputStream, Console.InputEncoding, false, inputBuffer.Length)) {
            Console.SetIn(reader);
            new Solver(Console.In, Console.Out).Run();
        }
#else
        Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
        new Solver(Console.In, Console.Out).Run();
        Console.Out.Flush();
#endif
    }

#pragma warning disable IDE0052
    private readonly TextReader cin;
    private readonly TextWriter cout;
#pragma warning restore IDE0052

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

#pragma warning disable IDE1006
#pragma warning disable IDE0051
    private int ni() { return NextInt(); }
    private int[] ni(int n) { return NextIntArray(n); }
    private long nl() { return NextLong(); }
    private long[] nl(int n) { return NextLongArray(n); }
    private double nd() { return NextDouble(); }
    private double[] nd(int n) { return NextDoubleArray(n); }
    private string ns() { return Next(); }
    private string[] ns(int n) { return NextArray(n); }
#pragma warning restore IDE1006
#pragma warning restore IDE0051
}

internal static class LinqPadExtension {
    [Conditional("DEBUG")]
    public static void Dump<T>(this T obj) {
#if DEBUG
        LINQPad.Extensions.Dump(obj);
#endif
    }
}

public class Scanner {
    private readonly TextReader Reader;
    private readonly CultureInfo ci = CultureInfo.InvariantCulture;

    private readonly char[] buffer = new char[2 * 1024];
    private int cursor = 0, length = 0;
    private string Token;
    private readonly StringBuilder sb = new StringBuilder(1024);

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

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

    public int NextInt() { return (int)NextLong(); }
    public long NextLong() {
        var s = Next();
        long r = 0;
        int i = 0;
        bool negative = false;
        if (s[i] == '-') {
            negative = true;
            i++;
        }
        for (; i < s.Length; i++) {
            r = r * 10 + (s[i] - '0');
#if DEBUG
            if (!char.IsDigit(s[i])) throw new FormatException();
#endif
        }
        return negative ? -r : r;
    }
    public double NextDouble() { return double.Parse(Next(), ci); }
    public string[] NextArray(int size) {
        string[] array = new string[size];
        for (int i = 0; i < size; i++) {
            array[i] = Next();
        }

        return array;
    }
    public int[] NextIntArray(int size) {
        int[] array = new int[size];
        for (int i = 0; i < size; i++) {
            array[i] = NextInt();
        }

        return array;
    }

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

        return array;
    }

    public double[] NextDoubleArray(int size) {
        double[] array = new double[size];
        for (int i = 0; i < size; i++) {
            array[i] = NextDouble();
        }

        return array;
    }

    public string Next() {
        if (Token == null) {
            if (!StockToken()) {
                throw new InvalidOperationException();
            }
        }
        var token = Token;
        Token = null;
        return token;
    }

    public bool HasNext() {
        if (Token != null) {
            return true;
        }

        return StockToken();
    }

    private bool StockToken() {
        while (true) {
            sb.Clear();
            while (true) {
                if (cursor >= length) {
                    cursor = 0;
                    if ((length = Reader.Read(buffer, 0, buffer.Length)) <= 0) {
                        break;
                    }
                }
                var c = buffer[cursor++];
                if (33 <= c && c <= 126) {
                    sb.Append(c);
                } else {
                    if (sb.Length > 0) break;
                }
            }

            if (sb.Length > 0) {
                Token = sb.ToString();
                return true;
            }

            return false;
        }
    }
}