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High School Seat Picker

note

This is a Beginner problem

Prompt​

You will create a program that will assign seats to a user for a high school sports game.

  • Create an array of available seats ["3A", "4C", "5F"...]
  • Prompt the user to choose whether they want a random seat given to them, or they want to choose their own seats.
  • If they want a random seat, print a random available seat for them.
  • If they want to choose a seat, then prompt them to input a seat. If that seat isn't available, ask them again. Keep asking until they input a valid seat.

Your program should have a function that has at least one parameter, that handles both cases (random or picking).

Example output:

Would you like to have a random seat, or pick one? (random/pick) >> random
Your seat is 3A!
Would you like to have a random seat, or pick one? (random/pick) >> pick
What seat would you like? > Z82
That seat is not available. Try again > 3A
Your seat is 3A!

Example Solution​

Our algorithm should be as follows:

  • Initialize an array availableSeats, which has the available seats.
  • Create a function seatPicker(choice), expecting "random" or "pick" for the choice parameter.
    • In this function, there are two cases:
    • If choice is random, then:
      • Pick a random number from 0 to availableSeats.length - 1
      • Print the seat from availableSeats at that index
    • If choice is pick, then:
      • Start a while loop that runs while the user hasn't selected a valid seat:
        • In the while loop, ask the user for a seat
        • Check if that seat is in availableSeats:
          • If it is, then return the seat and stop the while loop.
          • Else, tell them to try again.
  • Ask the user whether they want a random seat or to pick, and save their response in choice.
  • Call seatPicker(choice)
const availableSeats = ["3A", "3B", "3C", "3D", "3E", "4A", "4B", "4D", "B7", "A8", "B9", "Z3"];

// Parameter: choice (string), represents the choice that the user wants for the seat
function seatPicker(choice) {
	if (choice === "random") {
        const randomNumber = Math.random() * (availableSeats.length - 1);
        const chosenIndex = Math.round(randomNumber);
        const chosenSeat = availableSeats[chosenIndex];

        console.log("Your seat is", chosenSeat);

    } else if (choice === "pick") {

        let hasChosenAvailableSeat = false;
        
        while (hasChosenAvailableSeat === false) {
            const chosenSeat = prompt("Pick your seat: ");

            // they chose an available seat
            if (availableSeats.includes(chosenSeat)) { 
                console.log("Your seat is", chosenSeat);
                hasChosenAvailableSeat = true;
            } else { // they chose an invalid seat
                console.log("That seat is not available.");
            }
        }

    }
}

const choice = prompt("Would you like to pick a seat or get a random seat? (random/pick)");
seatPicker(choice);


Note: Math.random()​

info

Did you understand these lines?

const randomNumber = Math.random() * (availableSeats.length - 1);
const chosenIndex = Math.round(randomNumber);
const chosenSeat = availableSeats[chosenIndex];

Remember that Math.random() returns a random decimal from 0 to 1 (not including 1). We want a random number from 0 to availableSeats.length - 1, so we multiply the random number by availableSeats.length - 1, so the range is correct. Next, we round the result so we can properly index the array. Finally, we declare and initalize chosenSeat to the element at the randomly chosen index of availableSeats.

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