/lab-js-problems-arrays-objects

JavaScript Problems

Numbers & Strings

var numbers = [1,12,4,18,9,7,11,3,101,5,6];
var strings = ['this','is','a','collection','of','words'];

array.reduce - find the largest number

var largestValue = ___;
console.log('largest number: ' + largestValue);

array.reduce - find the longest string

var longest = ___;
console.log('longest word: ' + longest);

array.filter - find all even numbers

var evens = ___;
console.log('even numbers: ' + evens);

array.filter - find all odd numbers

var odds = ___;
console.log('odds numbers: ' + odds);

array .filter - find words that contain 'is'

var wordsWithIs = ___;
console.log('words containing is: ' + wordsWithIs);

array.map - return an array with all numbers squared (x^2)

var squared = ___;

console.log('squared array: ' + squared);

array.every - assert that all numbers are divisible by 3

var divisibleByThree = ___;
console.log('All numbers divisible by three: ' + divisibleByThree);

array.join - zip two arrays together

var joined = ___;
console.log('joined even and odd arrays: ' + joined);

array.sort - sort the joined array from smallest to largest

var sorted = ___;
console.log('sorted array ' + sorted);

remove the last word from strings

var lastWord = ___;
console.log('popped word: ' + lastWord);

put a new word "yeah" in the array

___;
console.log('strings: ' + strings);

remove the first word in the array

var word = ___;
console.log('removed from start: ' + word);
console.log('strings: ' + strings);

place a new word "this" at the start of the array

___;
console.log('added to start: ' + 'this');
console.log('strings: ' + strings);

grab a subset of elements, first 3 elements

var sliced = ___;;
console.log('subset: '  + sliced);
console.log('strings: ' + strings);

replace the first three elements, with "test" and "123"

var x = ___;
console.log('removed: ' + x + ' and replaced with test, 123');
console.log(strings);

Customers

Given the following array, return an array that:

  • contains only customers whose firstname starts with 'J',
  • where objects have a unique key name that combines the firstname and lastname,
  • and sorted alphabetically
var customers = [
    { firstname : 'Joe',  lastname : 'Blogs'},
    { firstname : 'John', lastname : 'Smith'},
    { firstname : 'Dave', lastname : 'Jones'},
    { firstname : 'Jack', lastname : 'White'}
];

var result = [
    { name : 'Jack White'},
    { name : 'Joe Blogs'},
    { name : 'John Smith'}
];

Happy Coding!!