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//!========XORSHIFT RANDOMIZER========
//! A class using George Marsaglia's "Xorshift-128" algorithm.
//! Provides very fast and quality sequence
//! of 2^{128}-1 32-bit random numbers.
class htRandomizer
{
unsigned long seed,x,y,z,w;
public:
htRandomizer(unsigned long state=GetTickCount()) {RndSet(state);}
//! Randomization.
void RndSet(unsigned long state=123456789)
{seed=x=state,y=362436069,z=521288629,w=88675123;}
//! More randomization.
void RndShift() {RndSet(Rnd());}
//! For farther restore a sequence we need to know a seed.
unsigned long RndSeed(void) {return seed;}
//! Returns unsigned long in [0..ULONG_MAX].
unsigned long Rnd()
{
unsigned long t=(x^(x<<11)); x=y;y=z;z=w;
return(w=(w^(w>>19))^(t^(t>>8)));
}
//! Returns float in [0,1)
float Rndf()
{
unsigned long f=Rnd();
f=0x3f800000U|(0x007fffffU&f);
float val=*(float*)&f-1.f;
return val;
}
//! Returns double in [0,1].
double Rndd()
{
return Rnd()/(double)0xffffffffUL; //! ULONG_MAX.
}
//! Returns unsigned long in [num1..num2].
unsigned long Rnd(unsigned long num1,unsigned long num2)
{
if(num1==num2) return num1;
float rnd=Rndf();
if(num2>num1)
return num1+(unsigned long)(rnd*(num2-num1+1));
else
return num2+(unsigned long)(rnd*(num1-num2+1));
}
//! Returns int in [num1..num2].
int Rndi(int num1,int num2)
{
if(num1==num2) return num1;
float rnd=Rndf();
if(num2>num1)
return num1+(int)(rnd*(num2-num1+1));
else
return num2+(int)(rnd*(num1-num2+1));
}
//! Returns float in [num1..num2).
float Rndf(float num1,float num2)
{
if(num1==num2) return num1;
float rnd=Rndf();
if(num2>num1)
return (num2-num1)*rnd+num1;
else
return (num1-num2)*rnd+num2;
}
//! Returns double in [num1..num2].
double Rndd(double num1,double num2)
{
if(num1==num2) return num1;
double rnd=Rndd();
if(num2>num1)
return (num2-num1)*rnd+num1;
else
return (num1-num2)*rnd+num2;
}
//! Returns random boolean.
bool Rndb() {return Rnd()%2;}
//! Returns random sign.
int Rnds() {return Rndb()? 1:-1;}
};
Using:
htRandomizer htr;
int main()
{
for(int i=0;i<50;i++) cout<<htr.Rnd()<<endl;
getchar();
return 0;
}
