Discussion on: Daily Challenge #41 - Greed is Good

function score( dice ) {
  // Business rules of the game:
  //  v: the dice value
  //  c: the number of dice required to trigger the rule
  //  p: the points added each time the rule is triggered
  const scoringRules = [
    {v: 1, c: 3, p: 1000},
    {v: 6, c: 3, p: 600},
    {v: 5, c: 3, p: 500},
    {v: 4, c: 3, p: 400},
    {v: 3, c: 3, p: 300},
    {v: 2, c: 3, p: 200},
    {v: 1, c: 1, p: 100},
    {v: 5, c: 1, p: 50}
  ]

  // returns the score given a histogram mapping a dice value to the number of dice with that value
  const scoreForHistogram = counts => {
    let score = 0
    for (const {v, c, p} of scoringRules) {
      const ruleCount = Math.floor((counts[v] || 0) / c);
      counts[v] -= ruleCount * c;
      score += ruleCount * p;
    }
    return score;
  };

  // Generate the histogram required by scoreForHistogram
  const counts = [...Array(7)].map(v=>0);// note that the rest of the logic uses 1-indexed arrays, so we need 7 entries to get a valid counts[6] entry
  for (const v of dice) counts[v]++;

  return scoreForHistogram(counts)
}