Find my mistake with the random command

I'm writing a little routine that simulates the rolling of dice,
but it gives the same numbers in the same order every time
I run it, even if I recompile the code each time.

My random routine looks like
randomize();
roll=random(sides)+1;

I'm using Turbo C 4.5. Can you see any problem with the above?
I have stdlib.h and time.h included...

Thanks,
Jason F.
jfahy@sprint.ca

[Rick Blommers]

Hi Jason,

I don't see what you are doing wrong but you could try this:
----
#include <stdlib.h>
#include <stdio.h>
#include <time.h>

srand( (unsigned)time( NULL ) ); // is the same as randomize()
roll = rand()%sides + 1 // is the same as random()
---
randomize() and random() are not standard C !!
maybe in Borland, but not in Microsoft C,
so I advice you to use rand() and srand() like used above

Good Luck,

Rick Blommers
rbl@agp.nl

Try this (it will make your output look like dice too!):

#include <iostream.h>
#include <stdlib.h>
#include <time.h>

const int SIZE = 6;

int main()
{
int one, two, total;
srand(time(NULL));
char *DieA[SIZE] = {".", ":", ":.", "::", ":.:", ":::"};
char *DieB[SIZE] = {".", ":", ":.", "::", ":.:", ":::"};
one = rand()%6 + 1;
two = rand()%6 + 1;
total = one + two;
cout << "Die A is " << DieA[one-1] << endl;
cout << "Die B is " << DieB[two-1] << endl;
cout << "Total rolled was: " << total << "\n\n";
return 0;
}

[Chris Wheeler]

I'm not exactly sure how "randomize" works in Turbo C, but the usual problem with random numbers is the seed of the random number generator. Randomizing functions are really just an equation that operates on a number. If you start with the same number every time, your "random" numbers will become predictable for as many as you can remember. Try seeding the random number with an internal time function such as seconds since 1980 or something.

Chris R. Wheeler, MCP
Pensacola Christian College
Desktop Programmer
cwheeler@pcci.edu