randrange C

//random number generator from 1 to n
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define CHECKED 1
int *flag;
int* rand_range(limit)
{
    //random array generator
    int *random_nos, i, no, ctr = 0;
    random_nos = (int *) calloc(limit + 1, sizeof(int));
    flag = (int *) calloc(limit + 1, sizeof(int));
    srand(time(NULL));
    while (ctr < limit)
    {
        no = rand() % limit + 1;
        if (flag[no] != CHECKED)
        {
            flag[no] = CHECKED;
            random_nos[ctr] = no;
            ctr ++;
        }
    }
    return random_nos;
}
void print_list(int *ar, int size)
{
    int i;
    printf("\n");
    for (i = 0; i < size; i ++)
        printf("%d\t", ar[i]);
    printf("\n");
}
int main()
{
    int *ar, n;
    printf("\nEnter upper limit: ");
    scanf("%d", &n);
    ar = rand_range(n);
    print_list(ar, n);
    return 0;
}