Exercise – Operators & Control Structures

by jordwms

JavaScript

/**
 * Exercise:
 *
 * Get to know your control structures
 *
 * Work in the console, or use "console.log()" to output to the console from the script
 *
 * these browser based functions can be used
 *     alert("Message string"); // will alert a message to the user
 *     var val = prompt("Question string?"); // will prompt the user for a value and return the value
 *     confirm("Message string"); // will ask the user to confirm with an ok, or cancel, returning a boolean
 */

// 1)
// Ask the user for a number (using prompt())
var userNum = prompt('Give me a number.');
// Tell the user if it is even or odd (using alert())
// (hint: prompt() will always return a string)

function isOdd(num) { return num % 2;}

var evenOrOdd = isOdd(userNum) ? "odd." : "even.";
alert("The number you gave was " + evenOrOdd);

// 2)
// Ask the user how old they are (using prompt())
var userAge = prompt("What is your current age in years?");
                     
// If they are 70 or older, tell them they look great.
if(userAge >= 70) {
	alert("You look great!");

// If they are 18 or younger, tell them they should be in school.
} else if (userAge <= 18) {
	alert("You should be in school!");
} else {
// If they are between those ages, tell them to get a job.
	alert("Get a job!");
}

// 3) 
// We have an array of values
// Use a while() statement to go through each value of the array
// and add 1 to each number (but not strings)
// log the resulting array to the console

var myArray = [1,2,3,"Interlocutor", 4,5,6];
var i = 0; 

while( i < myArray.length ) {
    if(typeof myArray[i] === 'number') {
    	myArray[i] += 1;
    }
    
    i++;
}
console.log(myArray);

// 4)
// Make an array of people's names
var names = ["Ali", "Brad", "Charles"];
var namesConcat = "";
// Use a for statement to go through each and combine
// them into a single string separated by commas
for (var i = 0; i < names.length; i++) {
    namesConcat += names[i];
}
// Log the result to the console.
// ex result:...