Super7

[compudave]

Hi I'm taking the grade 11 Computer Info & Sci course. I'd like some help with this program. This program is supposed to randomly choose 7 numbers, the only problem is sometimes these numbers are chosen twice.

My question is, what can I add that will make the program not choose the same number twice?

Quote:

randomize
var i : int
put "Super7 Lottery Number Chooser"
for count : 1 ..7
randint(i, 1, 47)
put i
end for

[Chimaera]

easy, just set up 7 randints separately and make it redo itself if it is equal to a number that has already been selected. Ta da! 8)

[Tony]

no no no tsk tsk tsk

you do not to that I've already wrote up the code for generating a list of random unique numbers, it is here

[Chimaera]

Here's exactly what your program should be doing

<code>
randomize
var i, a, b, c, d, e,f : int
put "Super7 Lottery Number Chooser"
randint (a, 1, 47)
randint (b, 1, 47)
randint (c, 1, 47)
randint (d, 1, 47)
randint (e, 1, 47)
randint (f, 1, 47)
randint (i, 1, 47)
loop
if a = b or a = c or a = d or a = e or a = f or a = i
then
randint (a, 1, 47)
elsif b = a or b = c or b = d or b = e or b = f or b = i
then
randint (b, 1, 47)
elsif c = b or c = a or c = d or c = e or c = f or c = i
then
randint (c, 1, 47)
elsif d = b or d = c or d = a or d = e or d = f or d = i
then
randint (d, 1, 47)
elsif e = b or e = c or e = a or e = d or e = f or e = i
then
randint (e, 1, 47)
elsif f = b or f = c or f = a or f = e or f = d or f = i
then
randint (f, 1, 47)
elsif i = b or i = c or i = a or i = e or i = f or i = d
then
randint (i, 1, 47)
end if
exit when a not= b and a not= c and a not= d and a not= e and a not= f and a not= i
and b not= a and b not= c or b not= d and b not= e and b not= f and b not= i
and c not= b and c not= a and c not= d and c not= e and c not= f and c not= i
and d not= b and d not= c and d not= a and d not= e and d not= f and d not= i
and e not= b and e not= c and e not= a and e not= d and e not= f and e not= i
and f not= b and f not= c and f not= a and f not= e and f not= d and f not= i
and f not= b and f not= c and f not= a and f not= e and f not= d and f not= i
end loop
put a, " ", b, " ", c, " ", d, " ", e, " ", f, " ", i

</code>

[PaddyLong]

ohhh please noooo don't do it the way Chimaera says... that way is horrible... using wayyy more variables than you need.... sure that way works but it's not a very good way to do it

[compudave]

lol, yeah thanks for the coding but that's a lot of variables... i'm going to try and work with the other code...

[AsianSensation]

lol, Chimaera, what if someone wanted 100 different numbers?

by your method, then it would take (100(101))/2, or 5050 different comparisons.

codes have to be effiecient and clean,, and usually have to deal with any situation of it's type.

[Tony]

doesn't anyone ever look at my code I'll post it here, not just the link this time

code:

var randN:int %just to hold the number var numbers:array 1..47 of int for i:1..47 numbers(i):=i end for for decreasing i:47..40 randN := Rand.Int(1,i) put numbers(randN) , " "..     if randN not=i then     for a:randN+1..i     numbers(a-1):=numbers(a)     end for     end if end for

[Chimaera]

wow I am so shamed by tony =_= well actually tony didn't shame me, I shamed myself by putting up my cruddy code. I don't really think in terms of that, I just think of doing what the question asks specifically as opposed to allowing it to be more open ended and perhaps using it for other things in the future. Props to tony for doing that stuff though

[Tony]

heh, dont worry about that Chimaera

this comes with experience. Everybody starts off with programing a program that acomplishes a task, but with experience and knowledge, you'll begin to see a bigger picture. And as far as I know, when it comes to programming - there's a LOT of changes between original goal and final product.

Heh - here's an interesting consept you'll come across if you keep on programming long enough : [b]abstract classes[/i]. I learned them in Java 8) They are basically object parts that cannot be used directly, but other objects incorporate in themselves. Though you'd probly need to get into OOP first to understand.

[Chimaera]

btw what is this OOP stuff that you guys talk about sometimes. I've heard you guys use the term, but still have no idea just what it is.

[Tony]

OOP - Object Oriented Programming. It's a style of programming where you create interactive objects, rether then one continues code that flows one way.

It's possible to use OOP in Turing (WinOOT - Windows Object Oriented Turing but it's all a big lie. Noone but Catalyst uses OOP in turing ), you might touch onto it in C++ (I didn't ) but Java is where the fun is at in Java, everything is OOP. Heck, even your variables are objects - each containing it's own properties and methods that can be executed.

[Blade]

for the answer to the question... wouldn't it be much better to use a boolean array? because they way tony's doing it you are running a for loop a hella lotta times... maximizing execution time..

[Tony]

blade, you must be on drugs or something

Quote:

for decreasing i:47..40

thats 7 executions, exactly how many random numbers are needed

first for loop is just initialization of the array, something you would also need for a boolean array As I said this before - to randomly pick 1000th unique number, you would have a 1/1000 chance of landing the right number and a hell lots of if statments executed using boolean array method:lol:

[Blade]

code:

const num:10 var ii,temp:int:=0 var nums:array 1.. num of int var bool:array 1.. num of boolean for i:1..num   bool(i):=false end for loop   temp:=Rand.Int(1,num)   if (bool(temp) = false) then     bool(temp):=true     nums(ii):=temp     ii+=1   end if   exit when ii >= num end loop

if your numbers are between like 30 and 40 then chance your boolean array to 30 .. 40 and your Rand.Int between 30 and 40

it works for everything, and its simpler than yours, but i dont know about execution time