Re: [問題] 產生超過32767的亂數

[sjgau (sjgau)]

#include <cstdlib>
#include <iostream>

using namespace std;
// ----------------------------------------------

#include <math.h>
// ----------------------------------------------

//   rnd1(    &s1);
void rnd1(int *s1)
{
   double x1, x2, x3;

   x1= (double) (*s1);
   x2= x1*16807.0;
   x3= fmod(x2, 2147483647.0);

   (*s1)= (int) (x3 + 0.5);
}// end of rnd1()
// ----------------------------------------------

void init_rnd(int *ss)
{
   int s1, s2, ct1;

   s1= time(NULL);
   s2= s1;
   ct1= 0;

   while (s1 == s2) {
      // get new s1
      s1= time(NULL);
      ct1++;
   }
   // s1 <> s2

   *ss= (s1 + ct1);
}// end of init_rnd()
// ----------------------------------------------

int main(int argc, char *argv[])
{
   int s1, i;

   init_rnd(&s1);
   printf("\n s1= %d \n", s1);

   for (i=1;i<=20;i++) {
      rnd1(&s1);
      printf("s1= %12ld \n", s1);
   }
   system("pause");
   return EXIT_SUCCESS;
}// end of main()


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