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# random numbers

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I am trying to generate 9 random numbers that do not repeat. here is the code I am using.

srand(

unsigned(time(NULL)));

int x=0;

vector <int> Num_Array;

for(int i=1; i<=9; i++)
{
Num_Array.push_back(i);
}
random_shuffle(Num_Array.begin(),Num_Array.end());
player_O=Num_Array[x];
x++;


I am attempting to do some AI for a tic tac toe game.

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What's the question?

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I am doing what you suggested .

Posted Today, 04:35 PM

What's the question?

how do I generate 9 random numbers that do not repeat?

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use not Num_Array.push_back(i); but something like Num_Array.push_back(rand());

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And what is wrong with the code? What do you see? Does the example from cplusplus.com work for you? It's pretty much exactly what you are after.

http://www.cplusplus.com/reference/algorithm/random_shuffle/

My best guess is you forgot std:: or a header. Other than that I don't see anything fundamentally wrong with the code you posted. Perhaps you would like to clarify.

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use not Num_Array.push_back(i); but something like Num_Array.push_back(rand());

This fails the requirement, because it's possible that rand() will return the same number at least twice in the nine calls.

The only true way to do it is to shuffle the possible values, like shuffling a deck of cards, rather than randomly picking a card from a huge pile and hoping there are no duplicates.

I am doing what you suggested .

Posted Today, 04:35 PM

What's the question?

how do I generate 9 random numbers that do not repeat?
It looks like you did. Try telling us what you expected to happen, and what actually happened, and be as specific as possible. Edited by Ectara

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well thanks for all the help but I will take a long hard look at my game code and see what is wrong and correct it.

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well thanks for all the help but I will take a long hard look at my game code and see what is wrong and correct it.

...

Taking a "long hard look" won't help. You need to:

1. figure out what you want the code to do

2. verify it does what it you want it to

3. debug it to see why it doesn't

I think you got step 2 down. I am not sure you have done step 1. And step 3 can't be done without step 1. Before fixing your problem, you need to know what the problem is.

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I am more than willing to help, as I'm sure many of us are, but I can't see how the code that you posted doesn't meet the goal that you mentioned; I don't see anything wrong. This either means that there is a problem elsewhere that is causing unexpected results, or I don't know what your goal really is.

Start with making sure that I understand your goal, and I can devote as much time as you need in finding the solution. It looks as if it correctly generates a randomized vector of numbers 1 through 9, so either later on it isn't using these numbers properly, or you are looking for more than a randomized vector of numbers. Any hint would be helpful.

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well thanks for all the help but I will take a long hard look at my game code and see what is wrong and correct it.

Phil, I salute you.  You troll better than anyone I've met.  Congrats.

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