結果

問題 No.1312 Snake Eyes
ユーザー EmKjpEmKjp
提出日時 2020-12-09 01:33:56
言語 C#(csc)
(csc 3.9.0)
結果
AC  
実行時間 262 ms / 2,000 ms
コード長 7,832 bytes
コンパイル時間 1,051 ms
コンパイル使用メモリ 118,936 KB
実行使用メモリ 26,312 KB
最終ジャッジ日時 2024-05-07 18:06:58
合計ジャッジ時間 5,623 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge3
このコードへのチャレンジ
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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 24 ms
24,256 KB
testcase_01 AC 24 ms
22,064 KB
testcase_02 AC 25 ms
24,112 KB
testcase_03 AC 23 ms
23,808 KB
testcase_04 AC 25 ms
24,060 KB
testcase_05 AC 24 ms
24,060 KB
testcase_06 AC 25 ms
24,060 KB
testcase_07 AC 24 ms
24,192 KB
testcase_08 AC 25 ms
25,912 KB
testcase_09 AC 24 ms
23,980 KB
testcase_10 AC 25 ms
23,984 KB
testcase_11 AC 26 ms
26,104 KB
testcase_12 AC 24 ms
23,928 KB
testcase_13 AC 25 ms
23,980 KB
testcase_14 AC 25 ms
23,928 KB
testcase_15 AC 25 ms
23,800 KB
testcase_16 AC 25 ms
26,096 KB
testcase_17 AC 26 ms
26,312 KB
testcase_18 AC 24 ms
21,940 KB
testcase_19 AC 25 ms
23,804 KB
testcase_20 AC 25 ms
26,036 KB
testcase_21 AC 26 ms
25,968 KB
testcase_22 AC 25 ms
25,900 KB
testcase_23 AC 26 ms
25,972 KB
testcase_24 AC 25 ms
25,996 KB
testcase_25 AC 24 ms
24,056 KB
testcase_26 AC 25 ms
26,176 KB
testcase_27 AC 24 ms
24,120 KB
testcase_28 AC 25 ms
23,984 KB
testcase_29 AC 25 ms
24,000 KB
testcase_30 AC 24 ms
23,956 KB
testcase_31 AC 26 ms
26,164 KB
testcase_32 AC 25 ms
24,000 KB
testcase_33 AC 24 ms
21,944 KB
testcase_34 AC 25 ms
23,800 KB
testcase_35 AC 25 ms
23,932 KB
testcase_36 AC 25 ms
26,048 KB
testcase_37 AC 25 ms
26,180 KB
testcase_38 AC 25 ms
24,060 KB
testcase_39 AC 26 ms
26,132 KB
testcase_40 AC 25 ms
21,680 KB
testcase_41 AC 26 ms
23,872 KB
testcase_42 AC 25 ms
24,060 KB
testcase_43 AC 25 ms
23,804 KB
testcase_44 AC 26 ms
23,880 KB
testcase_45 AC 25 ms
24,112 KB
testcase_46 AC 26 ms
26,100 KB
testcase_47 AC 26 ms
26,092 KB
testcase_48 AC 41 ms
24,240 KB
testcase_49 AC 34 ms
23,924 KB
testcase_50 AC 32 ms
25,928 KB
testcase_51 AC 28 ms
24,060 KB
testcase_52 AC 35 ms
23,980 KB
testcase_53 AC 32 ms
23,876 KB
testcase_54 AC 35 ms
22,064 KB
testcase_55 AC 28 ms
23,672 KB
testcase_56 AC 34 ms
23,928 KB
testcase_57 AC 30 ms
22,064 KB
testcase_58 AC 33 ms
24,064 KB
testcase_59 AC 28 ms
22,072 KB
testcase_60 AC 29 ms
24,060 KB
testcase_61 AC 37 ms
21,812 KB
testcase_62 AC 32 ms
25,840 KB
testcase_63 AC 26 ms
21,968 KB
testcase_64 AC 25 ms
23,868 KB
testcase_65 AC 27 ms
24,120 KB
testcase_66 AC 26 ms
23,804 KB
testcase_67 AC 24 ms
23,988 KB
testcase_68 AC 24 ms
24,052 KB
testcase_69 AC 25 ms
24,060 KB
testcase_70 AC 35 ms
21,944 KB
testcase_71 AC 30 ms
21,812 KB
testcase_72 AC 25 ms
23,992 KB
testcase_73 AC 25 ms
23,888 KB
testcase_74 AC 25 ms
24,192 KB
testcase_75 AC 24 ms
23,876 KB
testcase_76 AC 262 ms
24,156 KB
testcase_77 AC 36 ms
25,904 KB
testcase_78 AC 35 ms
24,108 KB
testcase_79 AC 32 ms
24,184 KB
testcase_80 AC 34 ms
23,808 KB
testcase_81 AC 34 ms
24,252 KB
testcase_82 AC 39 ms
24,000 KB
testcase_83 AC 41 ms
23,928 KB
testcase_84 AC 36 ms
24,060 KB
testcase_85 AC 36 ms
24,000 KB
testcase_86 AC 40 ms
21,944 KB
testcase_87 AC 31 ms
26,228 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;
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 {
    public void Run() {
        var n = nl();
        // y = (1 + p + p^2 + .. p^x)
        // n = k * y
        // x の範囲は小さい
        // x,y を固定すると p は二分探索で求められる
        long ans = n + 1;

        foreach (var d in Divisors(n)) {
            var k = d;
            var y = n / d;
            if (k >= y) continue;
            for (int x = 2; x < 60; x++) {
                MoveUntil(1, n, p => {
                    try {
                        checked {
                            long v = 0;
                            for (int i = 0; i < x; i++) {
                                v *= p;
                                v += 1;
                            }
                            if (v <= y) {
                                if (y == v) {
                                    if (k < p) {
                                        ans = Math.Min(ans, p);
                                    }
                                }
                                return true;
                            } else {
                                return false;
                            }
                        }
                    } catch (OverflowException) {
                        return false;
                    }
                });
            }
        }
        cout.WriteLine(ans);
    }

    public static long MoveUntil(long ok, long ng, Predicate<long> predicate) {
        if (ok == ng) throw new Exception();
        while (Math.Abs(ok - ng) > 1) {
            var mid = (ok + ng) >> 1;
            if (predicate(mid)) {
                ok = mid;
            } else {
                ng = mid;
            }
        }
        return ok;
    }

    public static List<long> Divisors(long x) {
        var ret = new List<long>();
        for (long i = 1; i * i <= x; i++) {
            if (x % i == 0) {
                ret.Add(i);
                if (i != x / i) {
                    ret.Add(x / i);
                }
            }
        }
        ret.Sort();
        return ret;
    }
}


// PREWRITEN CODE BEGINS FROM HERE

static public class StringExtensions {
    static public string JoinToString<T>(this IEnumerable<T> source, string separator = " ") {
        return string.Join(separator, source);
    }
}

internal partial class Solver : Scanner {
    static readonly int? StackSizeInMebiByte = null; //50;
    public static void StartAndJoin(Action action, int maxStackSize) {
        var thread = new Thread(new ThreadStart(action), maxStackSize);
        thread.Start();
        thread.Join();
    }

    public static void Main() {
#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 });
        if (StackSizeInMebiByte.HasValue) {
            StartAndJoin(() => new Solver(Console.In, Console.Out).Run(), StackSizeInMebiByte.Value * 1024 * 1024);
        } else {
            new Solver(Console.In, Console.Out).Run();
        }
        Console.Out.Flush();
#endif
    }

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

    public Solver(TextReader reader, TextWriter writer)
        : base(reader) {
        cin = reader;
        cout = writer;
        cerr = Console.Error;
    }

    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
}

#if DEBUG
internal static class LinqPadExtension {
    public static string TextDump<T>(this T obj) {
        if (obj is IEnumerable) return (obj as IEnumerable).Cast<object>().JoinToString().Dump();
        else return obj.ToString().Dump();
    }
    public static T Dump<T>(this T obj) {
        return 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 checked((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 Exception();
            }
        }
        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;
        }
    }
}
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