Address Book - using objects

gistfile1.js

// Codeacademy.com project, "Address Book"
// the functions input and output information about objects collected in the array.
// Note that there's no class; you have to define the attributes explicitly when creating the object.

var contacts = [];

function printPerson (person) {
    console.log(person.firstName + " " + person.lastName);
}

function list() {
    var items = contacts.length;
    for (i=0;i<items;i++) {
        printPerson(contacts[i]);
    }
}

function add(firstName,lastName,email,telephone){
    var friend = {
        firstName: firstName,
        lastName: lastName,
        phoneNumber: telephone,
        email: email
    };
    contacts[contacts.length] = friend;
}

function search(lastName) {
    var items = contacts.length;
    for(i=0;i<items;i++) {
        if(lastName===contacts[i].lastName){
            printPerson(contacts[i]);
        }
    }
}