Srand () w/ range
That code was for a range between 9 to 15, but I'm having problems with getting it into the negative range. The range I'm trying to get is -5 to 14.Code:srand(time(NULL)); range = (15-9) + 1; printf(" %d", rand() % range + 9);
Any help is appreciated, thank you in advance.
>The range I'm trying to get is -5 to 14.
Code:srand(time(NULL)); range = (14 - -5) + 1; printf(" %d", rand() % range - 5);
Do it after, since rand()'s return value is 0 to RAND_MAX.
[edit]nevermind...[/edit]
awesome, thanks swoopy. I wasn't sure if 14 - - 5 would work, because i would assume it be 20. but then writing out the number % 20 - 5 would work as well. Thanks!
I guess to generalize you could write:
Code:num = (rand() % (upper - lower + 1)) + lower
I want to be able to expand what we're doing. how would I go about only choosing intervals randomly from the range?
So between -5 to 14 but intervals of 3. Selecting only the possibilities of :
-5, -2, 1, 4, 7, 10, 13
Well you've got 7 different numbers so:
lower would be -5 in this case.Code:num = 3 * (rand() % 7) + lower;
Starting from 0,
Now adjust for starting from -5Code:/* interval of 3 from 0 */ if(num % 3 == 0)
awesome, thanks guy ;D
