Same number from rand inside a function when called multiple times, C

Question

I have a function to get a random number returned from function roll_dice however it seems to be a problem when i´m calling it agian, it gives me the same number, somehow its not given a new seed when called agian.

int roll_dice(void){
  int random_dice_numbers[2];
  int i = 0;
  int sum = 0;
  srand(time(NULL));

  for(i = 0; i < 2; i++){
    random_dice_numbers[i] = rand() % 6+1;


  }

  sum = random_dice_numbers[0] + random_dice_numbers[1];
  return sum;

}

int main(void){
int sum = 0;

sum = roll_dice();
printf("You rolled", sum);

sum = roll_dice();
printf("You rolled", sum);

return 0;
}

score 3 · Accepted Answer · edited Sep 19 '14 at 19:22

3

time(NULL) returns seconds and your function is very fast so you are probably seeding with the same number in both runs.

You should only seed your random number generator once.

edited Sep 19 '14 at 19:22

Surya

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answered Sep 19 '14 at 19:15

dohashi

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Yeah it was the problem, changed it to main. Worked like a charm – Nicco Sep 19 '14 at 19:19
1

The best way to thanks is by accepting the answer which helped. :) – Surya Sep 19 '14 at 19:23

Same number from rand inside a function when called multiple times, C

1 Answers1