functions.js

"use strict";

/**
 * TODO:
 * Create a function called 'sayHello' that takes a parameter 'name'.
 * When called, the function should return a message that says hello to the passed in name.
 *
 * Example
 * > sayHello("codeup") // returns "Hello, codeup!"
 */
function sayHello(name) {
    return "Hello, " + name + "!";
}

/**
 * TODO:
 * Call the function 'sayHello' and pass your name as a string literal argument.
 * Store the result of the function call in a variable named 'helloMessage'.
 *
 * console.log 'helloMessage' to check your work
 */
var helloMessage = sayHello("Lili");
console.log(helloMessage);
/**
 * TODO:
 * Store your name as a string in a variable named 'myName', and pass that
 * variable to the 'sayHello' function. You should see the same output in the
 * console.
 */
var myName = "Lili";
sayHello(myName);
console.log(sayHello(myName));
console.log(sayHello("Lucy"));
// Don't modify the following line, it generates a random number between 1 and 3
// and stores it in a variable named random
var random = Math.floor((Math.random() * 3) + 1);

/**
 * TODO:
 * Create a function called 'isTwo' that takes a number as a parameter.
 * The function should return a boolean value based on whether or not the passed
 * number is the number 2.
 *
 * Example
 * > isTwo(1) // returns false
 * > isTwo(2) // returns true
 * > isTwo(3) // returns false
 *
 * Call the function 'isTwo' passing the variable 'random' as a argument.
 *
 * console.log *outside of the function* to check your work (you should see a
 * different result everytime you refresh the page if you are using the random
 * number)
 */
function isTwo(a) {
    return a === 2;
}

console.log(isTwo(random));
console.log(random);

/**
 * TODO:
 * Create a function named 'calculateTip' to calculate a tip on a bill at a
 * restaurant. The function should accept a tip percentage and the total of the
 * bill, and return the amount to tip
 *
 * Examples:
 * > calculateTip(0.20, 20) // returns 4
 * > calculateTip(0.25, 25.50) // returns 6.375
 * > calculateTip(0.15, 33.42) // returns 5.013
 */
function calculateTip(a, b) {
    return a * b;
}

calculateTip(0.20, 20);
console.log(calculateTip(0.20, 20));
calculateTip(0.25, 25.50);
console.log(calculateTip(0.25, 25.50));
calculateTip(0.15, 33.42);
console.log(calculateTip(0.15, 33.42));
/**
 * TODO:
 * Use prompt and alert in combination with your calculateTip function to
 * prompt the user for the bill total and a percentage they would like to tip,
 * then display the dollar amount they should tip
 */
var percentage = Number(prompt("What percentage do you want to tip?"));
var totalBill = Number(prompt("How much is the total bill?"));
alert("you should tip $" + calculateTip(percentage, totalBill));
console.log("you should tip $" + calculateTip(percentage, totalBill));

// alert("you should tip $" + calculateTip(Number(prompt("Tip percentage")), Number(prompt("total bill?"))));

/**
 * TODO:
 * Create a function named `applyDiscount`. This function should accept a price
 * (before a discount is applied), and a discount percentage (a number between 0
 * and 1). It should return the result of applying the discount to the original
 * price.
 *
 * Example:
 * > var originalPrice = 100;
 * > var dicountPercent = .2; // 20%
 * > applyDiscount(originalPrice, dicountPercent) // 80
 *
 * > applyDiscount(45.99, 0.12) // 40.4712
 */
function applyDiscount(price, discount) {
    if (discount > 0 && discount < 1) {
        return price - price * discount;
    }
}

applyDiscount(45.99, 0.12);
console.log("price after discount: $" + applyDiscount(45.99, 0.12));