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unsigned long RL;
RL=((unsigned long)rand()<<16)|(((unsigned long)rand()<<8)&0x0000FF00UL)|((unsigned long)rand()&0x000000FFUL);
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define RANDOM_MAX 0x7FFFFFFF
static long my_do_rand(unsigned long* value)
{
/*
这个算法保证所产生的值不会超过(2^31 - 1)
这里(2^31 - 1)就是 0x7FFFFFFF。而 0x7FFFFFFF
等于127773 * (7^5) + 2836,7^5 = 16807。
整个算法是通过:t = (7^5 * t) mod (2^31 - 1)
这个公式来计算随机值,并且把这次得到的值,作为
下次计算的随机种子值。
*/
long quotient, remainder, t;
quotient = *value / 127773L;
remainder = *value % 127773L;
t = 16807L * remainder - 2836L * quotient;
if (t <= 0)
t += 0x7FFFFFFFL;
return ((*value = t) % ((unsigned long)RANDOM_MAX + 1));
}
static unsigned long next = 1;
int my_rand(void)
{
return my_do_rand(&next);
}
void my_srand(unsigned int seed)
{
next = seed;
}
int main()
{
int i;
my_srand((unsigned)(time(NULL)));
for (i = 0; i < 100; i++)
{
if (i % 10 == 0)
printf("\n");
printf("%d\t", my_rand() % 99 + 1);
}
system("pause");
return 0;
}
#include <stdio.h>
#include <stdlib.h>
#define RANDOM_MAX 0x7FFFFFFF
static long my_do_rand(unsigned long *value)
{
/*
这个算法保证所产生的值不会超过(2^31 - 1)
这里(2^31 - 1)就是 0x7FFFFFFF。而 0x7FFFFFFF
等于127773 * (7^5) + 2836,7^5 = 16807。
整个算法是通过:t = (7^5 * t) mod (2^31 - 1)
这个公式来计算随机值,并且把这次得到的值,作为
下次计算的随机种子值。
*/
long quotient, remainder, t;
quotient = *value / 127773L;
remainder = *value % 127773L;
t = 16807L * remainder - 2836L * quotient;
if (t <= 0)
t += 0x7FFFFFFFL;
return ((*value = t) % ((unsigned long)RANDOM_MAX + 1));
}
static unsigned long next = 1;
int my_rand(void)
{
return my_do_rand(&next);
}
void my_srand(unsigned int seed)
{
next = seed;
}
#include <time.h>
int main()
{
int i;
my_srand((unsigned)(time(NULL)));
for (i = 0; i < 100; i++)
{
if (i % 10 == 0)
printf("\n");
printf("%d\t", my_rand() % 99 + 1);
}
system("pause");
return 0;
}