Solution in javascript. I don't think this is necessarily the correct way to do this, just one way. I wanted to figure out an efficient way to use the data structures that are available in Perl to solve this. Setting up the data is really what I want to learn

// Day 21: RPG Simulator 20XX
// boss's stats
// Hit Points: 100
// Damage: 8
// Armor: 2

function part1() {
  const WEAPONS = new Map([
    ["dagger", { cost: 8, damage: 4, armor: 0 }],
    ["shortsword", { cost: 10, damage: 5, armor: 0 }],
    ["warhammer", { cost: 25, damage: 6, armor: 0 }],
    ["longsword", { cost: 40, damage: 7, armor: 0 }],
    ["greataxe", { cost: 74, damage: 8, armor: 0 }],
  ]);

  const ARMOR = new Map([
    ["nothing", { cost: 0, damage: 0, armor: 0 }],
    ["leather", { cost: 13, damage: 0, armor: 1 }],
    ["chainmail", { cost: 31, damage: 0, armor: 2 }],
    ["splintmail", { cost: 53, damage: 0, armor: 3 }],
    ["bandedmail", { cost: 75, damage: 0, armor: 4 }],
    ["platemail", { cost: 102, damage: 0, armor: 5 }],
  ]);

  const RINGS = new Map([
    ["nothing", { cost: 0, damage: 0, armor: 0 }],
    ["damage+1", { cost: 25, damage: 1, armor: 0 }],
    ["damage+2", { cost: 50, damage: 2, armor: 0 }],
    ["damage+3", { cost: 100, damage: 3, armor: 0 }],
    ["defense+1", { cost: 20, damage: 0, armor: 1 }],
    ["defense+2", { cost: 40, damage: 0, armor: 2 }],
    ["defense+3", { cost: 80, damage: 0, armor: 3 }],
  ]);

  const BOSS = new Map([
    ["damage", 8],
    ["armor", 2],
    ["health", 100],
  ]);

  const PLAYER = new Map([
    ["damage", 0],
    ["armor", 0],
    ["health", 100],
  ]);

  const getTotalStats = (weapon, armor, leftRing, rightRing) => {
    return {
      cost: weapon.cost + armor.cost + leftRing.cost + rightRing.cost,
      damage: weapon.damage + armor.damage + leftRing.damage + rightRi
+ng.damage,
      armor: weapon.armor + armor.armor + leftRing.armor + rightRing.a
+rmor,
    };
  };

  const hitPerSecond = (defenderHealth, defenderArmor, attackerDmg) =>
    Math.ceil(defenderHealth / Math.max(1, attackerDmg - defenderArmor
+));
  const makeMove = (boss, player) =>
    hitPerSecond(boss.get("health"), boss.get("armor"), player.get("da
+mage")) <=
    hitPerSecond(player.get("health"), player.get("armor"), boss.get("
+damage"));

  function* possibleBundles() {
    for (let weapon of WEAPONS.values()) {
      for (let armor of ARMOR.values()) {
        for (let leftRing of RINGS.values()) {
          for (let rightRing of RINGS.values()) {
            if (rightRing.cost !== leftRing.cost)
              yield getTotalStats(weapon, armor, leftRing, rightRing);
          }
        }
      }
    }
  }

  let result = Infinity;
  for (let bundle of possibleBundles()) {
    PLAYER.set("damage", bundle.damage).set("armor", bundle.armor);
    if (makeMove(BOSS, PLAYER)) result = Math.min(result, bundle.cost)
+;
  }

  console.log(result);
}

part1();
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