Submission #7635238


Source Code Expand

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

namespace CF16_final_C
{
    class Program
    {
        public static void Solve(Input input)
        {
            var n = input.NextInt();
            var m = input.NextInt();

            var used = new bool[m];
            var uf = new UnionFind(m);
            for (int i = 0; i < n; i++)
            {
                var k = input.NextInt();
                var l = input.NextInt(k, -1);

                for (int j = 0; j < l.Length; j++)
                {
                    uf.Merge(l[0], l[j]);
                    used[l[j]] = true;
                }
            }

            var usedCount = used.Count(x => x);
            for (int i = 0; i < m; i++)
            {
                if (!used[i])
                {
                    continue;
                }
                if (uf.SameCount(i) != usedCount)
                {
                    Console.WriteLine("NO");
                    return;
                }
            }

            Console.WriteLine("YES");
        }

        /// <summary>
        /// 重み付きUF木
        /// </summary>
        class UnionFind
        {
            int[] Rank { get; set; }
            int[] Size { get; set; }
            int[] ParentId { get; set; }
            int[] DiffWeight { get; set; }

            /// <summary>
            /// 
            /// </summary>
            /// <param name="size">ノードの総数</param>
            public UnionFind(int size)
            {
                this.Rank = new int[size];
                this.Size = Enumerable.Repeat(1, size).ToArray();
                this.ParentId = Enumerable.Range(0, size).ToArray();
                this.DiffWeight = new int[size];
            }

            /// <summary>
            /// 同一の親を持つか
            /// </summary>
            /// <param name="x"></param>
            /// <param name="y"></param>
            /// <returns></returns>
            public bool Same(int x, int y)
            {
                return FindRoot(x) == FindRoot(y);
            }

            /// <summary>
            /// 指定ノードのrootを返す
            /// </summary>
            /// <param name="x"></param>
            /// <returns></returns>
            public int FindRoot(int x)
            {
                if (x != this.ParentId[x])
                {
                    // 経路中のノードのパラメータを更新しておく
                    var root = FindRoot(this.ParentId[x]);
                    this.DiffWeight[x] += this.DiffWeight[this.ParentId[x]];
                    this.ParentId[x] = root;
                }

                return this.ParentId[x];
            }

            /// <summary>
            /// 親経路との重さを返す
            /// </summary>
            /// <param name="x"></param>
            /// <returns></returns>
            public int Weight(int x)
            {
                FindRoot(x);

                return this.DiffWeight[x];
            }

            /// <summary>
            /// x,yが同一の親を持つ場合、Weightの差分(y-x)を返す
            /// </summary>
            /// <param name="x"></param>
            /// <param name="y"></param>
            /// <returns></returns>
            public int Weight(int x, int y)
            {
                return Weight(y) - Weight(x);
            }

            /// <summary>
            /// 重みをつけて合体する
            /// </summary>
            /// <param name="x"></param>
            /// <param name="y"></param>
            /// <param name="w"></param>
            public void Merge(int x, int y, int w = 0)
            {
                w += Weight(x) - Weight(y);

                x = FindRoot(x);
                y = FindRoot(y);

                if (x == y) return;

                if (this.Rank[x] < this.Rank[y])
                {
                    this.ParentId[x] = y;
                    this.Size[y] += this.Size[x];
                    this.DiffWeight[x] = -w;
                }
                else
                {
                    this.ParentId[y] = x;
                    this.Size[x] += this.Size[y];
                    this.DiffWeight[y] = w;

                    if (this.Rank[x] == this.Rank[y])
                    {
                        this.Rank[x]++;
                    }
                }
            }

            /// <summary>
            /// xと同じ親を持つノードの数
            /// </summary>
            /// <param name="x"></param>
            /// <returns></returns>
            public int SameCount(int x)
            {
                x = FindRoot(x);

                return this.Size[x];
            }
        }

        #region Main
        public static void Main(string[] args)
        {
            // 出力が少ないときはこれをセットする方が時間かかるけれど
            // そのときにTLEするのはアルゴリズムが悪いせいだし、まあ良しとする
            var needsFlushOutput = true;
            if (needsFlushOutput)
            {
                // 細かく出力しないようにする
                var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
                Console.SetOut(sw);
            }

            // 通常は引数無しで、ファイルから読み出したい場合はpath指定する
            var input = new Input();

            // 仮想的に標準入力をセットする
            // テスト入力したまま提出することがままあるので……
#if DEBUG
            input.SetText("");
#endif

            Solve(input);

            Console.Out.Flush();
        }
        #endregion

        #region Competitive Template
#pragma warning disable CS0414
        static readonly int MOD = (int)1e9 + 7;
        static readonly int[] dx = { 1, 0, -1, 0 };
        static readonly int[] dy = { 0, 1, 0, -1 };
        /// <summary> 左上が原点 </summary>
        static readonly char[] dir = { 'R', 'U', 'L', 'D' };
#pragma warning restore CS0414

        public class Input
        {
            // 変な改行コードがたまに混じっているので、一応セパレート指定する
            // スペース単独指定の方がもちろん早い
            static readonly char[] separator = { ' ', '\r', '\n' };
            readonly StreamReader sr;
            readonly Queue<string> queue;

            /// <summary>
            /// 特定のファイルから読み出したい場合はpath指定する
            /// </summary>
            public Input(string path = "")
            {
                queue = new Queue<string>();

                if (string.IsNullOrEmpty(path)) { sr = new StreamReader(Console.OpenStandardInput()); }
                else { sr = new StreamReader(path); }
            }

            /// <summary>
            /// 入力予約
            /// </summary>
            public void SetText(IEnumerable<string> items)
            {
                foreach (var item in items)
                    SetText(item);
            }

            /// <summary>
            /// 入力予約
            /// </summary>
            public bool SetText(string s)
            {
                if (string.IsNullOrEmpty(s)) return false;

                foreach (var elem in s.Trim().Split(separator, StringSplitOptions.RemoveEmptyEntries))
                    queue.Enqueue(elem);

                return true;
            }

            /// <summary>
            /// 要素が存在するか
            /// </summary>
            public bool Any() => queue.Any() || Read();

            /// <summary>
            /// 内部queueに入力からの値をsplitして格納する
            /// </summary>
            bool Read()
            {
                if (!SetText(sr.ReadLine())) return false;

                if (!queue.Any()) return Read();

                return queue.Any();
            }

            /// <summary>
            /// 次のstringを一つ読み込む
            /// </summary>
            public string Next()
            {
                if (!queue.Any() && !Read()) return "";

                return queue.Dequeue();
            }

            /// <summary>
            /// 指定個数queueにたまるまでenqueueし続ける
            /// </summary>
            bool Accumulate(int n)
            {
                while (queue.Count() < n)
                    if (!Read()) return false;

                return true;
            }

            public int NextInt() => int.Parse(Next());
            public long NextLong() => long.Parse(Next());
            public double NextDouble() => double.Parse(Next());

            /// <summary>
            /// n個の要素をparseして、それぞれにoffsetをaddした配列を返す
            /// </summary>
            T[] NextT<T>(int n, T offset, Func<string, T> parse, Func<T, T, T> add)
            {
                if (!Accumulate(n)) return null;

                var a = new T[n];

                for (int i = 0; i < n; i++)
                    a[i] = add(parse(queue.Dequeue()), offset);

                return a;
            }

            public string[] Next(int n) => NextT(n, "", x => x, (x, y) => x);
            public int[] NextInt(int n, int offset = 0) => NextT(n, offset, int.Parse, (x, y) => x + y);
            public long[] NextLong(int n, long offset = 0) => NextT(n, offset, long.Parse, (x, y) => x + y);
            public double[] NextDouble(int n, double offset = 0.0) => NextT(n, offset, double.Parse, (x, y) => x + y);
        }

        static class Utils
        {
            public static T Max<T>(params T[] objs) => objs.Max();
            public static T Min<T>(params T[] objs) => objs.Min();

            /// <summary>
            /// vでfillされたT[d1][d2]配列を作成する
            /// </summary>
            public static T[][] Create2DArray<T>(int d1, int d2, T v)
            {
                return
                    Enumerable.Repeat(0, d1).Select(_ =>
                    Enumerable.Repeat(v, d2).ToArray()).ToArray();
            }

            /// <summary>
            /// vでfillされたT[d1][d2][d3]配列を作成する
            /// </summary>
            public static T[][][] Create3DArray<T>(int d1, int d2, int d3, T v)
            {
                return
                    Enumerable.Repeat(0, d1).Select(_ =>
                    Enumerable.Repeat(0, d2).Select(__ =>
                    Enumerable.Repeat(v, d3).ToArray()).ToArray()).ToArray();
            }
        }
        #endregion
    }
}

Submission Info

Submission Time
Task C - Interpretation
User tetora1011
Language C# (Mono 4.6.2.0)
Score 400
Code Size 11120 Byte
Status AC
Exec Time 134 ms
Memory 23764 KB

Judge Result

Set Name sample dataset1 dataset2
Score / Max Score 0 / 0 200 / 200 200 / 200
Status
AC × 2
AC × 12
AC × 27
Set Name Test Cases
sample sample-01.txt, sample-02.txt
dataset1 sample-01.txt, sample-02.txt, 01-01.txt, 01-02.txt, 01-03.txt, 01-04.txt, 01-05.txt, 01-06.txt, 01-07.txt, 01-08.txt, 01-09.txt, 01-10.txt
dataset2 sample-01.txt, sample-02.txt, 01-01.txt, 01-02.txt, 01-03.txt, 01-04.txt, 01-05.txt, 01-06.txt, 01-07.txt, 01-08.txt, 01-09.txt, 01-10.txt, 02-01.txt, 02-02.txt, 02-03.txt, 02-04.txt, 02-05.txt, 02-06.txt, 02-07.txt, 02-08.txt, 02-09.txt, 02-10.txt, 02-11.txt, 02-12.txt, 02-13.txt, sample-01.txt, sample-02.txt
Case Name Status Exec Time Memory
01-01.txt AC 29 ms 13396 KB
01-02.txt AC 28 ms 9300 KB
01-03.txt AC 28 ms 9300 KB
01-04.txt AC 29 ms 11348 KB
01-05.txt AC 28 ms 9300 KB
01-06.txt AC 28 ms 11348 KB
01-07.txt AC 28 ms 13396 KB
01-08.txt AC 28 ms 11348 KB
01-09.txt AC 28 ms 11348 KB
01-10.txt AC 29 ms 11348 KB
02-01.txt AC 82 ms 19040 KB
02-02.txt AC 125 ms 15540 KB
02-03.txt AC 81 ms 17120 KB
02-04.txt AC 117 ms 19040 KB
02-05.txt AC 119 ms 15712 KB
02-06.txt AC 114 ms 19040 KB
02-07.txt AC 126 ms 17760 KB
02-08.txt AC 121 ms 15412 KB
02-09.txt AC 134 ms 19040 KB
02-10.txt AC 105 ms 21720 KB
02-11.txt AC 103 ms 23764 KB
02-12.txt AC 105 ms 21204 KB
02-13.txt AC 103 ms 21072 KB
sample-01.txt AC 28 ms 13396 KB
sample-02.txt AC 27 ms 11348 KB