Submission #2407330


Source Code Expand

using System;
using System.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Debug;
using SB = System.Text.StringBuilder;
//using System.Numerics;
using static System.Math;
namespace Program {
    public class Solver {
        Random rnd = new Random(0);
        public void Solve() {
            var n = ri;
            var m = ri;
            var X = rl;
            var f = new int[m];
            var t = new int[m];
            var w = new int[m];
            var set = new DisjointSet(n);
            for (int i = 0; i < m; i++)
            {
                f[i] = ri - 1; t[i] = ri - 1; w[i] = ri;
            }
            var G = Enumerate(n, x => new List<KeyValuePair<int, long>>());

            var sum = 0L;
            foreach (var id in Enumerate(m, x => x).OrderBy(x => w[x]))
            {
                if (set.Unite(f[id], t[id]))
                {
                    sum += w[id];
                    G[f[id]].Add(new KeyValuePair<int, long>(t[id], w[id]));
                    G[t[id]].Add(new KeyValuePair<int, long>(f[id], w[id]));
                }
            }
            if (sum > X)
            {
                Console.WriteLine(0); return;
            }
            var dist = Enumerate(n, x => new long[n]);
            for (int i = 0; i < n; i++)
            {
                Action<int, int, long> dfs = null;
                dfs = (prev, cur, v) =>
                {
                    dist[i][cur] = v;
                    foreach (var e in G[cur]) if (e.Key != prev) dfs(cur, e.Key, Max(v, e.Value));
                };
                dfs(-1, i, 0);
            }
            var eq = 0;
            var over = 0;
            for (int i = 0; i < m; i++)
            {
                var d = w[i] - dist[f[i]][t[i]];
                if (d == X - sum) eq++;
                else if (d > X - sum) over++;
            }
            ModInt ans = 0;
            if (X == sum)
            {
                ans += (ModInt.Pow(2, n - 1) - 2) * ModInt.Pow(2, m - (n - 1));
                ans += 2 * (ModInt.Pow(2, eq - (n - 1)) - 1) * ModInt.Pow(2, over);
            }
            else
            {
                ans += 2 * (ModInt.Pow(2, eq) - 1) * ModInt.Pow(2, over);
            }
            Console.WriteLine(ans);
        }
        const long INF = 5L << 60;
        static int[] dx = { -1, 0, 1, 0 };
        static int[] dy = { 0, 1, 0, -1 };
        const string URDL = "URDL";
        int ri { get { return sc.Integer(); } }
        long rl { get { return sc.Long(); } }
        double rd { get { return sc.Double(); } }
        string rs { get { return sc.Scan(); } }
        public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput());

        static T[] Enumerate<T>(int n, Func<int, T> f) {
            var a = new T[n];
            for (int i = 0; i < n; ++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();
        try
        {
            solver.Solve();
            Console.Out.Flush();
        }
        catch { }
    }
}
#endregion
#region Ex
namespace Program.IO {
    using System.IO;
    using System.Text;
    using System.Globalization;

    public class Printer: StreamWriter {
        public override IFormatProvider FormatProvider { get { return 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;
        public bool IsEndOfStream { get { return isEof; } }

        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


#region ModInt
public struct ModInt {
    public const long Mod = (int)1e9 + 7;

    public long num;
    public ModInt(long n) { num = n; }
    public override string ToString() { return num.ToString(); }
    public static ModInt operator +(ModInt l, ModInt r) { l.num += r.num; if (l.num >= Mod) l.num -= Mod; return l; }
    public static ModInt operator -(ModInt l, ModInt r) { l.num -= r.num; if (l.num < 0) l.num += Mod; return l; }
    public static ModInt operator *(ModInt l, ModInt r) { return new ModInt(l.num * r.num % Mod); }
    public static implicit operator ModInt(long n) { n %= Mod; if (n < 0) n += Mod; return new ModInt(n); }

    public static ModInt Pow(ModInt v, long k) { return Pow(v.num, k); }

    public static ModInt Pow(long v, long k) {
        long ret = 1;
        for (k %= Mod - 1; k > 0; k >>= 1, v = v * v % Mod)
            if ((k & 1) == 1) ret = ret * v % Mod;
        return new ModInt(ret);
    }
    public static ModInt Inverse(ModInt v) { return Pow(v, Mod - 2); }
}
#endregion
#region DisjointSet
public class DisjointSet {
    int[] par;
    byte[] rank;
    public DisjointSet(int n) {
        par = new int[n];
        for (int i = 0; i < n; i++)
            par[i] = -1;
        rank = new byte[n];
    }
    public int this[int id] {
        get {
            if ((par[id] < 0)) return id;
            return par[id] = this[par[id]];
        }
    }
    public bool Unite(int x, int y) {
        x = this[x]; y = this[y];
        if (x == y) return false;
        if (rank[x] < rank[y]) { var z = x; x = y; y = z; }
        par[x] += par[y];
        par[y] = x;
        if (rank[x] == rank[y])
            rank[x]++;
        return true;
    }
    public int Size(int x) { return -par[this[x]]; }
    public bool IsUnited(int x, int y) { return this[x] == this[y]; }

}
#endregion

Submission Info

Submission Time
Task E - Bichrome Spanning Tree
User camypaper
Language C# (Mono 4.6.2.0)
Score 900
Code Size 7502 Byte
Status AC
Exec Time 107 ms
Memory 21728 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 900 / 900
Status
AC × 4
AC × 52
Set Name Test Cases
Sample sample-01.txt, sample-02.txt, sample-03.txt, sample-04.txt
All 01.txt, 02.txt, 03.txt, 04.txt, 05.txt, 06.txt, 07.txt, 08.txt, 09.txt, 10.txt, 11.txt, 12.txt, 13.txt, 14.txt, 15.txt, 16.txt, 17.txt, 18.txt, 19.txt, 20.txt, 21.txt, 22.txt, 23.txt, 24.txt, 25.txt, 26.txt, 27.txt, 28.txt, 29.txt, 30.txt, 31.txt, 32.txt, 33.txt, 34.txt, 35.txt, 36.txt, 37.txt, 38.txt, 39.txt, 40.txt, 41.txt, 42.txt, 43.txt, 44.txt, 45.txt, 46.txt, 47.txt, 48.txt, sample-01.txt, sample-02.txt, sample-03.txt, sample-04.txt
Case Name Status Exec Time Memory
01.txt AC 95 ms 17504 KB
02.txt AC 96 ms 19552 KB
03.txt AC 82 ms 21600 KB
04.txt AC 106 ms 19552 KB
05.txt AC 107 ms 19680 KB
06.txt AC 97 ms 17504 KB
07.txt AC 104 ms 17504 KB
08.txt AC 95 ms 19552 KB
09.txt AC 107 ms 19552 KB
10.txt AC 107 ms 21728 KB
11.txt AC 82 ms 21600 KB
12.txt AC 102 ms 19552 KB
13.txt AC 105 ms 19552 KB
14.txt AC 93 ms 17376 KB
15.txt AC 82 ms 19552 KB
16.txt AC 30 ms 13420 KB
17.txt AC 96 ms 17504 KB
18.txt AC 30 ms 11404 KB
19.txt AC 104 ms 19680 KB
20.txt AC 30 ms 11404 KB
21.txt AC 99 ms 19552 KB
22.txt AC 105 ms 17632 KB
23.txt AC 104 ms 21600 KB
24.txt AC 102 ms 19552 KB
25.txt AC 101 ms 17504 KB
26.txt AC 83 ms 21600 KB
27.txt AC 95 ms 17504 KB
28.txt AC 105 ms 21600 KB
29.txt AC 100 ms 19552 KB
30.txt AC 101 ms 19552 KB
31.txt AC 103 ms 19552 KB
32.txt AC 103 ms 21600 KB
33.txt AC 94 ms 19424 KB
34.txt AC 81 ms 19552 KB
35.txt AC 32 ms 11540 KB
36.txt AC 32 ms 11540 KB
37.txt AC 31 ms 9492 KB
38.txt AC 95 ms 17504 KB
39.txt AC 101 ms 17504 KB
40.txt AC 104 ms 21600 KB
41.txt AC 84 ms 19552 KB
42.txt AC 94 ms 19424 KB
43.txt AC 99 ms 17376 KB
44.txt AC 28 ms 13380 KB
45.txt AC 102 ms 21600 KB
46.txt AC 104 ms 19552 KB
47.txt AC 102 ms 17504 KB
48.txt AC 80 ms 21472 KB
sample-01.txt AC 29 ms 11476 KB
sample-02.txt AC 29 ms 13524 KB
sample-03.txt AC 27 ms 11348 KB
sample-04.txt AC 29 ms 11476 KB