Generate “In-Range” Random Numbers in C

Question

I need to generated random numbers in the range [0, 10] such that:

• All numbers occur once.
• No repeated results are achieved.

Can someone pl

Answer 1

Try to create a randomize function, like this:

void randomize(int v[], int size, int r_max) {
    int i,j,flag;

    v[0] = 0 + rand() % r_max; // start + rand() % end
    /* the following cycle manages, discarding it,
the case in which a number who has previously been extracted, is re-extracted. */
    for(i = 1; i < size; i++) {
        do {
            v[i]= 0 + rand() % r_max;
            for(j=0; j

Then, simply call it passing an array v[] of 11 elements, its size, and the upper range:

randomize(v, 11, 11);

The array, due to the fact that it is passed as argument by reference, will be randomized, with no repeats and with numbers occur once.

Remember to call srand(time(0)); before calling the randomize, and to initialize int v[11]={0,1,2,3,4,5,6,7,8,9,10};