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random numbers

Started by phil67rpg May 21, 2013 at 11:24 PM 13 replies 2.2k views
Original Post
phil67rpg
phil67rpg

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.

alvaro
alvaro

What's the question?

phil67rpg
phil67rpg

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?

kaktusas2598
kaktusas2598

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

Deltron Zero and Automator.
Bacterius
Bacterius

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.

“If I understand the standard right it is legal and safe to do this but the resulting value could be anything.”
Ectara
Ectara

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.
phil67rpg
phil67rpg

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.

Bacterius
Bacterius

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.

“If I understand the standard right it is legal and safe to do this but the resulting value could be anything.”
Ectara
Ectara

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.

BeerNutts
BeerNutts

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.

My Gamedev Journal: 2D Game Making, the Easy Way

---(Old Blog, still has good info): 2dGameMaking
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phil67rpg
phil67rpg

what in the hell is trolling?

FLeBlanc
FLeBlanc

what in the hell is trolling?


See definition #2 here.
Ectara
Ectara



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.
Try as hard as I might to find good in these threads, I'm starting to agree with you.
frob
frob
Trolling generally implies malicious or other antisocial intent.


While I do agree some of his posts have a trolling style to them, they have been evolving along a normal (yet atypically slow) learning curve. My suspicion is that he is just a casual learner. I dislike his choice of C++ due to the added learning curve, but that is his choice to make.


If you feel like it is a troll, just move on to the next discussion thread.
Cornstalks
Cornstalks

If you feel like it is a troll, just move on to the next discussion thread.

Or, if you want to take it a step further, you can go to your profile settings, and unger 'Ignore' Preferences, opt to ignore his posts.

I'm not going to share my personal feelings here on the matter, other than to say I'm glad GD has this ignore feature.

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