Generating 5 random numbers between two numbers.?

Question

In ASP (classic asp)

how can I generate 5 unique random numbers (being each of them is greater than the previous one), between two numbers?

For example, I want to generate 5 numbers between 1 and 1000.

It must generate like these:

45-66-124-534-794

Answer 1

Although Jareh's solution will work, you'll notice that it will have a tendency to result in numbers that are close to the upper-bound.  To demonstrate, I just tried it a few times and got:

1) 257 586 866 945 946

2) 680 929 960 981 997

3) 633 922 992 993 996

4) 494 788 826 896 907

5) 843 964 994 996 997

6) 168 260 732 888 893

7) 84 653 928 975 992

The first value is nicely random, but as it goes on, you get progressively very high numbers.  In fact, the last value will be more than 900 about 91 percent of the time, when instead, the top number should be over 900 about 41 percent of the time.  In general with this method, you'll get numbers that are approximately in the ballpark of:

500 750 875 938 969

What you want to do instead is put the random numbers into an array and then sort the array.  I'm not an ASP guy so this may be full of bugs. If so, you should be able to fix them easily, but you want something like this:

Randomize

Dim Values(5),t,i,Tmp,Min,Count,Max

Min = 0 '*** Minimum value

Max = 1000 '*** Maximum value

Count = 5 '*** Number of values

for t= 1 to Count

  Values(t) = INT(((Max - Min) * Rnd) + Min)

next

'*** Ideally, you'd sort the Values array here.

'*** Unfortunately, it looks like there isn't a

'*** sort function in ASP? Hence, let's do it

'*** ourselves. But really, you'd write a QuickSort

'*** algorithm and use that.

for t= 1 to Count-1

  for i= t+1 to Count

    if(Values(t) < Values(i) then

      Tmp = Values(t)

      Values(t) = Values(i)

      Values(i) = Tmp

    end if

  next

next

'*** Ok, now it's sorted, so we can print them out.

for t= 1 to Count

  response.write (Values(t) & "<br>")

next

DaveE

Answer 2

Voooooooaaaallllllaaaa :

<%

Randomize

Dim LastMax,MIN,Num_of_Val,MAX,This_Rnd

This_Rnd = 0

Min = 0 '*** Minimum value

Max = 1000 '*** Maximum value

Num_of_Val = 5 '*** Number of value you want it to return

for t= 1 to Num_of_Val

do while This_Rnd <= MIn '*** loop until a greater value is returned

This_Rnd = INT(((Max - MIN) * Rnd) + Min) '*** Generate the random value

if t = 1 and This_Rnd >= ((Max - MIN) - (Num_of_Val + 1)) then This_Rnd = 0 '*** Check if the first return value will allow the application to the number of value requested

loop

Min = This_Rnd

response.write (This_Rnd & "<br>")

next

%>