d6r11.cpp

来自「工程算法 这是一个很有用的工程数值算法集锦」· C++ 代码 · 共 46 行

# include <iostream.h>
# include <math.h>
# include <iomanip.h>

void main()
{
    //program d6r11
    //driver for routine irbit2
    //calculate distribution of runs of zeros
	int nbin,ntries,iseed,i,j,iflg,ipts,n;
	double delay[16];
    nbin = 15;
	ntries = 10000;
    iseed = 111;
    for (i = 1; i<=nbin; i++)
	{
        delay[i] = 0.0;
    }
    ipts = 0;
    for (i = 1; i <=ntries; i++)
	{
        if (irbit2(iseed) == 1)
		{
            ipts = ipts + 1;
            iflg = 0;
            for (j = 1; j<=nbin; j++)
			{
                if ((irbit2(iseed) == 1) && (iflg == 0))
				{
                    iflg = 1;
                    delay[j] = delay[j] + 1.0;
                }
            }
        }
    }
    cout<< "Distribution of runs of n zeros"<<endl;
    cout<< "    n     probability    expected"<<endl;
	cout<<setprecision(6)<<setiosflags(ios::fixed);
    for (n = 1; n<=nbin; n++)
	{
        cout<<setw(5)<<n - 1;
        cout<<setw(14)<<delay[n] / double(ipts);
        cout<<setw(14)<<(1.0/ pow(2,n))<<endl;
    }
}