using System;

using System.Collections.Generic;

using System.Linq;

using XorShifts;

​

//XorShift Module

//using System;

//using System.Collections.Generic;

​

namespace XorShifts{

    class XorShift{

        private IEnumerator<uint> r;

        public static readonly Dictionary<string,uint> defaults=new Dictionary<string,uint>(){

            {"x",123456789},

            {"y",362436069},

            {"z",521288629},

            {"w",88675123}

        };

        public readonly Dictionary<string,uint> seeds;

        public uint randCount=0;

​

        public XorShift(uint? _w=null,uint? _x=null,uint? _y=null,uint? _z=null){

            uint w=_w ?? (uint)Environment.TickCount;

            uint x=_x ?? w<<13;

            uint y=_y ?? (w>>9)^(x<<6);

            uint z=_z ?? y>>7;

            seeds=new Dictionary<string,uint>(){

                {"x",x},{"y",y},{"z",z},{"w",w}

            };

            r=randGen(w,x,y,z);

        }

​

        public IEnumerator<uint> randGen(uint w,uint x,uint y,uint z){

            uint t;

            for(;;){

                t=x^(x<<11);

                x=y;

                y=z;

                z=w;

                yield return w=(w^(w>>19))^(t^(t>>8));

            }

        }

​

        public uint rand(){

            randCount++;

            r.MoveNext();

            return r.Current;

        }

​

        public int randInt(int min=0,int max=0x7FFFFFFF){

            return (int)(rand()%(max-min+1))+min;

        }

​

        public float randFloat(float min=0,float max=1){

            return (float)(rand()%0xFFFF)/0xFFFF*(max-min)+min;

        }

​

        public T[] shuffle<T>(T[] _arr){

            var arr=(T[])_arr.Clone();

            for(int i=0;i<=arr.Length-2;i++){

                int r=randInt(i,arr.Length-1);

                T tmp=arr[i];

                arr[i]=arr[r];

                arr[r]=tmp;

            }

            return arr;

        }

​

        public List<T> shuffle<T>(List<T> _arr){

            var arr=new List<T>(_arr);

            for(int i=0;i<=arr.Count-2;i++){

                int r=randInt(i,arr.Count-1);

                T tmp=arr[i];

                arr[i]=arr[r];

                arr[r]=tmp;

            }

            return arr;

        }

​

        public class defaultSeed:XorShift{

            public defaultSeed():base(

                defaults["w"],

                defaults["x"],

                defaults["y"],

                defaults["z"]

            ){}

        }

    }

}

//XorShift End

​

namespace TestXS{

    public class TestXS{

        public static void Main(){

            //XorShift乱数ジェネレータの初期化

            // 論文デフォルトシード

            var r_def=new XorShift.defaultSeed();

            // 固定値シード

            var r_const=new XorShift(100);

            // 時間シード

            var r=new XorShift();

            //デフォルトシード値の取得

            Console.WriteLine(">> defaults");

            foreach(var i in XorShift.defaults.Keys){

                Console.WriteLine("{0}:{1}",i,XorShift.defaults[i]);

            }

            //適用したシード値の取得

            Console.WriteLine(">> seeds in r");

            foreach(var i in r.seeds.Keys){

                Console.WriteLine("{0}:{1}",i,XorShift.defaults[i]);

            }

            //乱数の生データを取得

            Console.WriteLine(">> rand 0 to UInt32Max");

            for(int i=0;i<5;i++){

                Console.WriteLine(r_def.rand());

            }

            //0-100の乱数(100含む)を整数で取得

            Console.WriteLine(">> randInt 0 to 100");

            for(int i=0;i<5;i++){

                Console.WriteLine(r_const.randInt(0,100));

            }

            //0-1の乱数を浮遊小数点で取得

            Console.WriteLine(">> randFloat 0 to 1");

            for(int i=0;i<5;i++){

                Console.WriteLine(r.randFloat());

            }

            //静的配列のシャッフル

            //値渡しとなるので元の配列は破壊されない

            Console.WriteLine(">> shuffle Array");

            int[] a=Enumerable.Range(0,20).ToArray();

            Console.WriteLine(String.Join(", ",r.shuffle(a)));

            Console.WriteLine(String.Join(", ",a));

            //List<T>のシャッフル

            Console.WriteLine(">> shuffle List<T>");

            var b=new List<int>(Enumerable.Range(0,20));

            Console.WriteLine(String.Join(", ",r.shuffle(b)));

            Console.WriteLine(String.Join(", ",b));

            //今の乱数を回した回数

            Console.WriteLine(">> randCount in r");

            Console.WriteLine(r.randCount);

        }

    }

}