Random, non-repeating vector

[IWishIKnew]

I am making a Flash Card program and i am includeing a shuffling feature. When the user presses Space, the program will create a vector with a list of random numbers. There should be no repeats in the vector so that you get to see every card. The problem is, i can't seem to find the problem. Here is the portion of the code:

if(GetAsyncKeyState(VK_SPACE))
        {
            for(int sdck = 1; sdck <= deck.words; sdck++)
            {
                x = ((rand()%deck.words) + 1);
                if(x == 0)
                {
                    x++;
                }
                if(sdck != 1)
                {
                    for(int dk = 1; dk <= sdck; dk++)
                    {
                        while(x == shuffle[dk])
                        {
                            x = ((rand()%deck.words) + 1);
                            if(x == 0)
                            {
                                x++;
                            }
                        }
                    }
                }
                shuffle.push_back(x);
            }

what it should do is make a random number, check the vector (assuming we already have a value in the vector, hence while( != 1)) to see if we already have the same number entered, and if so create a new random number.

shuffle[0] is already initialized (though not shown in the post), so we start at 1, and work our way to deck.words (deck.words = the number of cards in our deck).

When the code has found a number not already in the vector, it should put it in. For some reason, though, I keep getting duplicate numbers. I can't figure this out, since the while loop should theoretically eliminate the possability of that... but i may be wrong. This is the first program i have written that incorporates a "rand()" function, so I'm not entirely educated on the behavior of the function or how it chooses it's numbers. I will say this though, i have seen some discrepenc ies in the randomizations. One such example is that whenever i exit the program and restart it, i will make it create a random number and the first number is always the same: 10.

So, long story short, I need help. lol

[JLBorges]

Fill up the vector with numbers 1, 2, 3, ..., N

The use std::random_shuffle() to get a random permutation of the sequence.
http://cplusplus.com/reference/algorithm/random_shuffle/

[IWishIKnew]

Thank you.