freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript-rpg-game/part-051.md

6.7 KiB

id title challengeType dashedName
5d6904b6e0696bdec46938f2 Part 51 0 part-51

--description--

There is a shorthand way to add or subtract from a variable called compound assignment. The long way to add to a variable is num = num + 5. The shorthand way is num += 5. It works the same way with subtraction.

Update both lines inside the buyHealth function to use compound assignment.

--hints--

See description above for instructions.

assert(
  buyHealth.toString().match(/gold\s*\-\=\s*10\;?/) &&
    buyHealth.toString().match(/health\s*\+\=\s*10\;?/)
);

--seed--

--before-user-code--

<!DOCTYPE html>
<html lang="en" >
<head>
  <meta charset="UTF-8">
  <title>RPG - Dragon Repeller</title>
  <style>
    body {
      background-color: darkblue;
    }
    #text {
      background-color: black;
      color: white;
      padding: 10px;
    }
    #game {
      max-width: 500px;
      max-height: 400px;
      background-color: lightgray;
      color: white;
      margin: 0 auto;
      padding: 10px;
    }
    #controls {
      border: 1px black solid;
      padding: 5px;
    }
    #stats {
      border: 1px black solid;
      color: black;
      padding: 5px;
    }
    #monsterStats {
      display: none;
      border: 1px black solid;
      color: white;
      padding: 5px;
      background-color: red;
    }
    .stat {
      padding-right: 10px;
    }
  </style>
</head>
<body>
<div id="game">
  <div id="stats">
    <span class="stat">XP: <strong><span id="xpText">0</span></strong></span>
    <span class="stat">Health: <strong><span id="healthText">100</span></strong></span>
    <span class="stat">Gold: <strong><span id="goldText">50</span></strong></span>
  </div>
  <div id="controls">
    <button id="button1">Go to store</button>
    <button id="button2">Go to cave</button>
    <button id="button3">Fight dragon</button>
  </div>
  <div id="monsterStats">
    <span class="stat">Monster Name: <strong><span id="monsterName"></span></strong></span>
    <span class="stat">Health: <strong><span id="monsterHealth"></span></strong></span>
  </div>
  <div id="text">Welcome to Dragon Repeller. You must defeat the dragon that is preventing people from leaving the town. You are in the town square. Where do you want to go? Use the buttons above.</div>
</div>

--after-user-code--

</body>
</html>

--seed-contents--

<script>
let xp = 0;
let health = 100;
let gold = 50;
let currentWeapon = 0;
let fighting;
let monsterHealth;
let inventory = ["stick"];

const button1 = document.querySelector('#button1');
const button2 = document.querySelector("#button2");
const button3 = document.querySelector("#button3");
const text = document.querySelector("#text");
const xpText = document.querySelector("#xpText");
const healthText = document.querySelector("#healthText");
const goldText = document.querySelector("#goldText");
const monsterStats = document.querySelector("#monsterStats");
const monsterNameText = document.querySelector("#monsterName");
const monsterHealthText = document.querySelector("#monsterHealth");

const locations = [
  {
    name: "town square",
    "button text": ["Go to store", "Go to cave", "Fight dragon"],
    "button functions": [goStore, goCave, fightDragon],
    text: "You are in the town square. You see a sign that says \"Store.\""
  },
  {
    name: "store",
    "button text": ["Buy 10 health (10 gold)", "Buy weapon (30 gold)", "Go to town square"],
    "button functions": [buyHealth, buyWeapon, goTown],
    text: "You enter the store."
  },
  {
    name: "cave",
    "button text": ["Fight slime", "Fight fanged beast", "Go to town square"],
    "button functions": [fightSlime, fightBeast, goTown],
    text: "You enter the cave. You see some monsters."
  }
];

// initialize buttons
button1.onclick = goStore;
button2.onclick = goCave;
button3.onclick = fightDragon;

function update(location) {  
  button1.innerText = location["button text"][0];
  button2.innerText = location["button text"][1];
  button3.innerText = location["button text"][2];
  button1.onclick = location["button functions"][0];
  button2.onclick = location["button functions"][1];
  button3.onclick = location["button functions"][2];
  text.innerText = location.text;
}

function goTown() {
  update(locations[0]);
}

function goStore() {
  update(locations[1]);
}

function goCave() {
  update(locations[2]);
}

function fightDragon() {
  console.log("Fighting dragon.");
}

function buyHealth() {
  gold = gold - 10;
  health = health + 10;
}

function buyWeapon() {
}

function fightSlime() {
}

function fightBeast() {
}

</script>

--solutions--

<script>
let xp = 0;
let health = 100;
let gold = 50;
let currentWeapon = 0;
let fighting;
let monsterHealth;
let inventory = ["stick"];

const button1 = document.querySelector('#button1');
const button2 = document.querySelector("#button2");
const button3 = document.querySelector("#button3");
const text = document.querySelector("#text");
const xpText = document.querySelector("#xpText");
const healthText = document.querySelector("#healthText");
const goldText = document.querySelector("#goldText");
const monsterStats = document.querySelector("#monsterStats");
const monsterNameText = document.querySelector("#monsterName");
const monsterHealthText = document.querySelector("#monsterHealth");

const locations = [
  {
    name: "town square",
    "button text": ["Go to store", "Go to cave", "Fight dragon"],
    "button functions": [goStore, goCave, fightDragon],
    text: "You are in the town square. You see a sign that says \"Store.\""
  },
  {
    name: "store",
    "button text": ["Buy 10 health (10 gold)", "Buy weapon (30 gold)", "Go to town square"],
    "button functions": [buyHealth, buyWeapon, goTown],
    text: "You enter the store."
  },
    {
    name: "cave",
    "button text": ["Fight slime", "Fight fanged beast", "Go to town square"],
    "button functions": [fightSlime, fightBeast, goTown],
    text: "You enter the cave. You see some monsters."
  }
];

// initialize buttons
button1.onclick = goStore;
button2.onclick = goCave;
button3.onclick = fightDragon;

function update(location) {  
  button1.innerText = location["button text"][0];
  button2.innerText = location["button text"][1];
  button3.innerText = location["button text"][2];
  button1.onclick = location["button functions"][0];
  button2.onclick = location["button functions"][1];
  button3.onclick = location["button functions"][2];
  text.innerText = location.text;
}

function goTown() {
  update(locations[0]);
}

function goStore() {
  update(locations[1]);
}

function goCave() {
  update(locations[2]);
}

function fightDragon() {
  console.log("Fighting dragon.");
}

function buyHealth() {
  gold -= 10;
  health += 10;
}

function buyWeapon() {
}

function fightSlime() {
}

function fightBeast() {
}
</script>