Don Colton's Risk Dice Roller

(Risk is a trademark of Parker Bros / Hasbro for their board game.)
Wikipedia Article, Attacking

How many attacking armies
How many defending armies
How many skirmishes (max)

Skirmish 1   6 6 5   3 2 attacker loses X, defender loses X
Skirmish 2   3 6 4   5 6 attacker loses X, defender loses X
Skirmish 3   4 2 3   6 6 attacker loses X, defender loses X
Skirmish 4   6 5 3   2 1 attacker loses X, defender loses X