一个非常简单的求随机数的算法

#include <stdio.h>
#include <windows.h>

unsigned long int next = 1;
unsigned int rand(void)
{
  next = next * 1103515245 + 12345;
  return (unsigned int)(next/65536) % 32768;
}

void srand(unsigned int seed)
{
  next = seed;
}

int main()
{ 
 srand(GetTickCount());

 for(int i=0; i<10; i++)
 {
  for(int j=0; j<10; j++)
   printf("%d ", rand());
  printf("\n");   
 }

 return 0;
}

也可如下：
 

随机数

#include <stdlib.h>

Srand( GetTickCount() );

Rand();