C return same array elements with srand

Question

The problem is that I have two different arrays but return elements are the same. This is basic question, but I am banging my head for two hours. I use srand function so that is not the problem, at least I think so.

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

void swap(int *a, int *b);
int* napraviNiz(int n);
void stampajNiz(int niz[], int n);
void trazi(int niz1[], int niz2[], int n);

int main(int argc, char *argv[])
{
    int n = 8;
    srand(time(NULL));
    int* niz1 = napraviNiz(n);   
    int* niz2 = napraviNiz(n);

    // Stampaj niz
    stampajNiz(niz1, n);
    stampajNiz(niz2, n);

  system("PAUSE");  
  return 0;
}

void swap(int *a, int *b)
{
    int c = *a;
    *a = *b;
    *b = c;
}

void stampajNiz(int niz[], int n)
{
    int i;
    for(i = 0; i < n; i++)
    {
        printf("%d ", niz[i]);
    }
    printf("\n");
}

int* napraviNiz(int n)
{

    int i;
    int *niz = (int)malloc(n*sizeof(int));
    /* Intializes random number generator */

    for (i = 0; i < n; i++)
    {
        niz[i] = rand()%n; //uzima random indeks od 1 do i
    }
    return niz;
}

Output:

3 3 2 5 7 9 1 2

Also `int *niz = (int)malloc(n*sizeof(int));` --> `int *niz = (int*)malloc(n*sizeof(int));` or `int *niz = malloc(n*sizeof(int));` — BLUEPIXY, Oct 29 '16 at 14:55
Yes, didn't see that. After adding new functions to it, i came to the similar problem. http://pastebin.com/SMRvbv2v, take a look at main, after calling two functions izmesajNiz to shuffle the array, a call stampajNiz to print, but that return the array with elements of last shuffle call. — Dusan Stojnic, Oct 29 '16 at 15:08
The value returned by `time(NULL)` only changes once per second. You've essentially initialised the generator twice with the same number, hence the same output. — enhzflep, Oct 29 '16 at 15:09
@DusanStojnic you use same array (So print same array (So same result)). — BLUEPIXY, Oct 29 '16 at 15:17
try `int* niz1 = izmesajNiz(arr, n); stampajNiz(niz1, n); int* niz2 = izmesajNiz(arr, n); stampajNiz(niz2, n);` — BLUEPIXY, Oct 29 '16 at 15:19
@BLUEPIXY I think the arrays are different. There is niz1 and niz2 — Dusan Stojnic, Oct 29 '16 at 15:20
@BLUEPIXY Yes, that works, but the problem is that i need to cal third function `trazi(niz1, niz2, n);` below that. Like that, the arrays pased through function would be the same. — Dusan Stojnic, Oct 29 '16 at 15:23
you want that `izmesajNiz` must return a copy of the input array. (E.g. by malloc and memcpy) — BLUEPIXY, Oct 29 '16 at 15:26

C return same array elements with srand

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