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two quick questions

two quick questions

(OP)
firstly, im trying to generate 'random' numbers between zero and 49 (guess what for).  currently im using:

time_t t;
srand(unsigned (time(&t)));
int num = (rand() % 49);

but as that stands, the numbers im getting dont seem very random. in fact they seem like theyre just being plucked from a sequential count through 0 - 49.  also, its wasting a lot of time in my while loop becuase the same number will be generated lots of times before it changes.  what more effective way is there of achieving this?

also, i have a simple array which im putting these numbers into "numbers[6]".  for my 6 numbers.  what sorta syntax would i need to use to sort it into ascending order using the qsort() function?  or failing that, what other simple sort algorithms are there that could be used?

cheers,

craig.

RE: two quick questions

why not use a simple sorting alg like bubble sort or selection sort and get done with it, and ur array size seems to b really small and no optimization is needed.

RE: two quick questions

The algo below is what I use for picking unique cards in the card games I used to write in Uni.  Basically pick one and put the one at the end in its position.
You could use selection sort to sort the numbers.

CODE

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

#define NOTPICKEDMAX 50
#define PICKEDMAX 6
int main(int argc, char* argv[])
{
int notpicked[NOTPICKEDMAX], n, p, remain, picked[PICKEDMAX], temp;

srand (time (0));

// Set up a list of numbers we can pick
for (n = 1; n < NOTPICKEDMAX; n++)
notpicked[n] = n;

remain = NOTPICKEDMAX;
for (p = 0; p < PICKEDMAX; p++)
{
// Get a number
remain--;
n = rand () % remain + 1;
picked[p] = notpicked[n];

// Move the one that we did not choose to the vacant position
notpicked[n] = notpicked[remain];
}

// Sort the numbers in order
for (p = 0; p < PICKEDMAX - 1; p++)
{
for (n = p + 1; n < PICKEDMAX; n++)
{
if (picked[p] > picked[n])
{
temp = picked[n];
picked[n] = picked[p];
picked[p] = temp;
}
}
}

// Print it out
for (p = 0; p < PICKEDMAX; p++)
printf ("%d ", picked[p]);
printf ("\n");
return 0;
}

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