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Exercise - If...else

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As a junior game developer of recreational games, you've been asked to start the development of a Blackjack game. Blackjack has some interesting rules on how to calculate points. You realize this game is a great opportunity to apply some Boolean logic you've learned.

Calculate a card hand

In Blackjack, the goal of the game is to win over the bank. You win by holding a score higher than the bank but less than or equal to 21.

1. Use the Azure Cloud Shell to create a file.

   touch app.js
   code .
   

2. Press Ctrl + S to save the file. Name the file blackjack.js.

3. Give it the following starter code:

   let cardOne = 7;
   let cardTwo = 5;
   let sum = cardOne + cardTwo; // 15
   

   Next, you'll add code that simulates taking one more card. Let's see what happens.

4. Add the following code:

   let cardThree = 7;
   sum += cardThree;
   if (sum > 21) {
     console.log('You lost');
     process.exit(1); // exit program
   }
   console.log(`You have ${sum} points`);
   

5. Save your changes, press Ctrl + Q to close the file, and then run the code.

   node blackjack.js
   

   You see the following output:

   You have 19 points
   

Add an opponent

Your opponent is the bank. Remember the rules. You win if you have a better score than the bank, or if the bank has over 21. Let's implement those rules.

1. Open the blackjack.js file.

   code blackjack.js
   

2. Add the following variables to represent the banks cards.

   let cardOneBank = 7;
   let cardTwoBank = 5;
   let cardThreeBank = 6;
   let cardFourBank = 4;
   

3. Next, add the following code to the end of the file.

   let bankSum = cardOneBank + cardTwoBank + cardThreeBank + cardFourBank;
   if (bankSum > 21 || (sum <= 21 && sum > bankSum)) {
    console.log('You win');
   } else {
     console.log('Bank wins');
   }
   

4. Save and close the file, and then run the code.

   node blackjack.js
   

   You see the following output:

   You have 19 points
   You win
   

Congratulations! You've successfully implemented some of the game rules from Blackjack by using Boolean logic and operators.

Here's the full code.

let cardOne = 7;
let cardTwo = 5;
let sum = cardOne + cardTwo; // 15
let cardOneBank = 7;
let cardTwoBank = 5;
let cardThreeBank = 6;
let cardFourBank = 4;

let cardThree = 7;
sum += cardThree;
if (sum > 21) {
  console.log('You lost');
}
console.log(`You have ${sum} points`);

let bankSum = cardOneBank + cardTwoBank + cardThreeBank + cardFourBank;

if (bankSum > 21 || (sum <= 21 && sum > bankSum)) {
  console.log('You win');
  process.exit(1); // exit program
} else {
  console.log('Bank wins');
}

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