Random # woes

can any one tell me why this random # generator only returns 42 every time

#include <stdAfx.h>
#include <iostream.h>
#include <stdlib.h> //for rand
//for printf
#include <time.h>

int rand_mid(int low,int high);

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

cout << endl;
cout << "you must role the dice here is the result of your role: ";
cout << rand_mid(1,100);


cout << endl;
return 0;
}
int rand_mid(int low, int high)
{
return low+rand()%(high-low+1);
}


I got this code out of the FAQ section

hm. haven't done random numbers in a while, but you need to seed it with the current time.

What i figured was rand just takes the seed you give it, does a whole bunch of operations and gives you a result. However, you seeded it with a constant, and therefore it gives the same result. MSDN help files give u the correct code and they tell you bout seeding. But yeh, u need to use time somehow.

cow

You need to seed rand with the srand() function

The problem is that if i seed it with the time and that function gets used over and over again its actually not random because each time you do it you can tell what the next number is gonna be

its because its counting too slow maybe i need to have the number cycle in faster time increments

Thats usally happens when you seed more then once. srand should only be used once. After the first time rand uses last result to "reseed" itself

Yaa does anyone have any suggestions for a random # generator that can handle multiple executions over a reletivly short period of time
:(

There shouldn't be a need for anything else then srand(). just put it in your main() and it will seed all your rand() in all functions

Code:

---


#include <stdAfx.h>
#include <iostream.h>
#include <stdlib.h> //for rand
//for printf
#include <time.h>

int rand_mid(int low,int high);

int main(int argc, char* argv[])
{
  srand(time(NULL));
  cout << endl;
  cout << "you must role the dice here is the result of your role: ";
  cout << rand_mid(1,100);
  cout << endl;
  return 0;
}

int rand_mid(int low, int high)
{
  return low+rand()%(high-low+1);
}

---

Oh well ill just have to live with that

Nothing stoping you from doing this.

Code:

---

#include <stdAfx.h>
#include <iostream.h>
#include <stdlib.h> //for rand
//for printf
#include <time.h>

int rand_mid(int low,int high);

int main(int argc, char* argv[])
{
  srand(time(NULL));
  cout << endl;
  cout << "you must role the dice here is the result of your role: ";
  for(int i = 0; i < 100; i++)
  {
      cout << rand_mid(1,100);
      cout << endl;
  }
  return 0;
}

int rand_mid(int low, int high)
{
  return low+rand()%(high-low+1);
}

---

if you use srand just once, it will be about as random as u get. Seed it once then just rand the rest.

cow