shuffle array elements (assumes 52 integers stored in array)

void shuffle(int a) {
    int temp = 0, counter_deck = 0, counter_do_loop = 0, exchange_rand = 0, exchange_card = 0;
    for (counter_do_loop = 0; counter_do_loop < a; counter_do_loop++) {
        for (counter_deck = 0; counter_deck < 52; counter_deck++) {
            temp = cards[counter_deck];
            exchange_rand = (rand() % 52);
            exchange_card = cards[exchange_rand];
            cards[counter_deck] = cards[exchange_card];
            cards[exchange_card] = temp;
        }}
    return;
}