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A golden rule to remember is that we help those best, who help themselves.

Showing what you tried yourself, even when it failed, is always considered a good sign and the Monks will rush to your aid. Just asking for some code, is frowned upon as we are no code writing or homework solving establishment.

So, show the Monks some of your code and we will speak again!

A hint: have a look at the rand function.

So you have actually asked what can be a very complicated question. Here is one link for you: randomness

I made a little program to satisfy your requirement and then added a little histogram and a way to loop multiple times (now 10 times). Program rolls dice until it sees a 6, then stops. Along the way to the 6, it keeps track of other numbers rolled. The int(rand(max+1)) gives out numbers from 0..max.

#!/usr/bin/perl -w
use strict;

my %histo;
for (1..10)
{  
   my $count=0;      
   while ( (my $r = int(rand(6)) +1 ) != 6) 
   {                #int(rand(6) generates nums 0-5
     $count++;
     $histo{$r}++;
   }
 #update  ####  $count++;  # there is an off by one error below
   print "took $count tries to get a 6\n";
   $histo{6}++;
}
foreach my $side (sort keys %histo)
{
   print "number $side rolled $histo{$side} times\n";
}

__END__
took 18 tries to get a 6
took 5 tries to get a 6
took 9 tries to get a 6
took 1 tries to get a 6
took 3 tries to get a 6
took 1 tries to get a 6
took 1 tries to get a 6
took 0 tries to get a 6
took 15 tries to get a 6
took 13 tries to get a 6

number 1 rolled 15 times
number 2 rolled 17 times
number 3 rolled 11 times
number 4 rolled 15 times
number 5 rolled 8 times
number 6 rolled 10 times
[download]

my $count=0;      
while ( (my $r = int(rand(6)) +1 ) != 6) 
{                #int(rand(6) generates nums 0-5
     $count++;
}
print "took ++$count tries to get a 6\n";
[download]

took 0 tries to get a 6
[download]

I've got a tournament backgammon match on Monday. If you can tell me how to get some sixes without throwing the dice, I'd be ever so grateful.

Yours not very sincerely, :-)

John Davies

Ha, a off by error! was ok for histo, but not $count. The general idea of how to do it remains the same as well as comments on imperfections in the standard rand() function. the link I provided is a good starting place.

good luck in your backgammon match!

all the numbers have already occured. the visual display is just proof that they occured in a particular sequence.
mathematical true randomness can never be reached, as you would need an infinitely large set (number of dice throws.)
in real life a dice can actually land on edge, and also any number of factors can introduce a bias. a program/script to generate dice throws or such, is a limited model.
if this is indeed some kind of dice throwing pretend problem, it should clearly define the limits/assumptions. as the required output for this excercise can change quite a bit depending on these assumptions.
the hardest line to type correctly is: stty erase ^H

The program I think you are asking for:

#!/usr/bin/perl
use warnings;                 
use strict;                   

use constant UPPER_LIMIT => 6;

my ( @numbers, $count );
while ( @numbers < UPPER_LIMIT ) {
    my $guess = int 1 + rand UPPER_LIMIT;
    push @numbers, $guess unless grep $_ == $guess, @numbers;
    ++$count;
    }                       

print                       
    map( "$_\n", @numbers ),
    "How many times to get to ", UPPER_LIMIT, " is $count\n";

__END__
[download]

How the program should really be written:

#!/usr/bin/perl
use warnings;
use strict;

use List::Util qw/ shuffle /;

use constant UPPER_LIMIT => 6;

my @numbers = shuffle 1 .. UPPER_LIMIT;

print
    map( "$_\n", @numbers ),
    "How many times to get to ", UPPER_LIMIT, " always ONE\n";

__END__
[download]

Should be written? I've never seen a die like that :)
Update: I understand the spec this way:

while ($n = int (rand 6) ){
  print 6-$n,"\n";
  $count++;
}
print "6\nTried ",1+$count," times.\n";
[download]