#338668 (C#(csc)) No.811 約数の個数の最大化

• 問題: No.811 約数の個数の最大化
• ユーザー: 紙ぺーぱー
• 提出日時: 2019-04-14 15:52:54
• 言語: C#(csc) (csc 3.9.0)
• 結果: AC
• 実行時間: 45 ms / 2,000 ms
• コード長: 4,449 bytes
• コンパイル時間: 1,788 ms
• コンパイル使用メモリ: 115,428 KB
• 実行使用メモリ: 24,720 KB
• 最終ジャッジ日時: 2023-10-19 06:15:18
• 合計ジャッジ時間: 3,341 ms
• ジャッジサーバーID （参考情報）: judge15 / judge13

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	26 ms; 24,720 KB
testcase_01	AC	26 ms; 24,720 KB
testcase_02	AC	45 ms; 24,720 KB
testcase_03	AC	27 ms; 24,716 KB
testcase_04	AC	27 ms; 24,720 KB
testcase_05	AC	27 ms; 24,716 KB
testcase_06	AC	28 ms; 24,720 KB
testcase_07	AC	27 ms; 24,716 KB
testcase_08	AC	36 ms; 24,720 KB
testcase_09	AC	31 ms; 24,716 KB
testcase_10	AC	31 ms; 24,720 KB
testcase_11	AC	35 ms; 24,716 KB
testcase_12	AC	30 ms; 24,720 KB
testcase_13	AC	38 ms; 24,720 KB
testcase_14	AC	43 ms; 24,720 KB

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.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Trace;
using SB = System.Text.StringBuilder;
//using System.Numerics;
using static System.Math;
using Number = System.Int64;
namespace Program {
    public class Solver {
        Random rnd = new Random(0);
        public void Solve() {
            var n = ri;
            var k = ri;
            var a = f(n);
            Debug.WriteLine(a.AsJoinedString());
            var cnt = new int[n + 1];
            for (int i = 1; i <= n; i++) {
                for (int j = i; j <= n; j += i) cnt[j]++;
            }
            Debug.WriteLine(cnt.AsJoinedString());
            var u = 0;
            var v = 0;
            for (int i = 1; i < n; i++) {
                var p = 0;
                var val = i;
                foreach (var x in a) if (val % x == 0) {
                        p++;
                        val /= x;
                    }
                Debug.WriteLine($"{i} {p}");
                if (p >= k && cnt[i] > u) {
                    u = cnt[i];
                    v = i;
                }
            }
            Console.WriteLine(v);
        }
        List<int> f(int n) {
            var ret = new List<int>();
            for (int i = 2; i <= n; i++) {
                while (n % i == 0) {
                    ret.Add(i);
                    n /= i;
                }
            }
            if (n != 1) ret.Add(n);
            return ret;
        }

        const long INF = 1L << 60;
        int ri => sc.Integer();
        long rl => sc.Long();
        double rd => sc.Double();
        string rs => sc.Scan();
        public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput());

        static IEnumerable<int> Rep(int n) => Enumerable.Range(0, n);
        static IEnumerable<int> RRep(int n) => Enumerable.Range(0, n).Reverse();
        static T[] Enumerate<T>(int n, Func<int, T> f) {
            var a = new T[n];
            for (int i = 0; i < a.Length; ++i) a[i] = f(i);
            return a;
        }
        static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }
    }
}
#region main
static class Ex {
    static public string AsString(this IEnumerable<char> ie) { return new string(ie.ToArray()); }
    static public string AsJoinedString<T>(this IEnumerable<T> ie, string st = " ") {
        return string.Join(st, ie);
    }
    static public void Main() {
        Console.SetOut(new Program.IO.Printer(Console.OpenStandardOutput()) { AutoFlush = false });
        var solver = new Program.Solver();
        solver.Solve();
        Console.Out.Flush();
    }
}
#endregion
#region Ex
namespace Program.IO {
    using System.IO;
    using System.Text;
    using System.Globalization;

    public class Printer : StreamWriter {
        public override IFormatProvider FormatProvider => CultureInfo.InvariantCulture;
        public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
    }

    public class StreamScanner {
        public StreamScanner(Stream stream) { str = stream; }

        public readonly Stream str;
        private readonly byte[] buf = new byte[1024];
        private int len, ptr;
        public bool isEof = false;

        private byte read() {
            if (isEof) return 0;
            if (ptr >= len) {
                ptr = 0;
                if ((len = str.Read(buf, 0, 1024)) <= 0) {
                    isEof = true;
                    return 0;
                }
            }
            return buf[ptr++];
        }

        public char Char() {
            byte b = 0;
            do b = read(); while ((b < 33 || 126 < b) && !isEof);
            return (char)b;
        }
        public string Scan() {
            var sb = new StringBuilder();
            for (var b = Char(); b >= 33 && b <= 126; b = (char)read()) sb.Append(b);
            return sb.ToString();
        }
        public string ScanLine() {
            var sb = new StringBuilder();
            for (var b = Char(); b != '\n' && b != 0; b = (char)read()) if (b != '\r') sb.Append(b);
            return sb.ToString();
        }
        public long Long() { return isEof ? long.MinValue : long.Parse(Scan()); }
        public int Integer() { return isEof ? int.MinValue : int.Parse(Scan()); }
        public double Double() { return isEof ? double.NaN : double.Parse(Scan(), CultureInfo.InvariantCulture); }
    }
}

#endregion