For a game of Dungeons & Dragons, each player starts by generating a character they can play with. This character has, among other things, six abilities; strength, dexterity, constitution, intelligence, wisdom and charisma. These six abilities have scores that are determined randomly. You do this by rolling four 6-sided dice and record the sum of the largest three dice. You do this six times, once for each ability.
Your character's initial hitpoints are 10 + your character's constitution modifier. You find your character's constitution modifier by subtracting 10 from your character's constitution, divide by 2 and round down.
Write a random character generator that follows the rules above.
For example, the six throws of four dice may look like:
Because constitution is 3, the constitution modifier is -4 and the hitpoints are 6.
Most programming languages feature (pseudo-)random generators, but few programming languages are designed to roll dice. One such language is Troll.