在C语言下实现0—1之间的随机数

随机数周期超长，且分布均匀，采用混洗方法避免重复

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <iostream.h>
#include <iomanip.h>
#include <time.h>
#define IM1 2147483563
#define IM2 2147483399
#define AM (1.0/IM1)
#define IMM1 (IM1-1)
#define IA1 40014
#define IA2 40692
#define IQ1 53668
#define IQ2 52774
#define IR1 12211
#define IR2 3791
#define NTAB 32
#define NDIV (1+IMM1/NTAB)
#define EPS 1.2e-7
#define RNMX (1.0-EPS)
unsigned int seed=0; //seed 为种子，要设为全局变量
void mysrand(long int i) //初始化种子
{
seed = -i;
}
double ran1(long *idum)
{
int j;
long k;
static long idum2=123456789;
static long iy=0;
static long iv[NTAB];
float temp;
if (*idum <= 0)
{
if (-(*idum) < 1) *idum=1;
else *idum = -(*idum);
idum2=(*idum);
for (j=NTAB+7;j>=0;j--) <