When I simulated just 100 trials, there were a number of identical net win/loss results that occured twice. Is my logic, or random number generation the problem?

One way to approach this is to strip out everything extraneous. This bisects the problem. If the symptoms go away, you have a pretty good idea which side of the line the problem lies on.

Something like the following may help you gain some insight: 

use Math::Random;
for ( 1 .. 100 ) {
    my $d1 = random_uniform_integer(1,1,6);
    my $d2 = random_uniform_integer(1,1,6);
    print $d1 + $2, "\n";
}

[download]
Does this produce results consistent with what you're seeing?

Is also helps, when asking people to review your code, to indent. Unindented code is hard to read, and many people will take one look at it and walk away.

Oh, and use strict; to avoid accidental globals like $roll.

In reply to Re: check my logic & a random number issue by dws
in thread check my logic & a random number issue by rmckillen

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