--- id: 587d78b2367417b2b2512b0f title: Remove Items from an Array with pop() and shift() challengeType: 1 forumTopicId: 301165 dashedName: remove-items-from-an-array-with-pop-and-shift --- # --description-- Both `push()` and `unshift()` have corresponding methods that are nearly functional opposites: `pop()` and `shift()`. As you may have guessed by now, instead of adding, `pop()` *removes* an element from the end of an array, while `shift()` removes an element from the beginning. The key difference between `pop()` and `shift()` and their cousins `push()` and `unshift()`, is that neither method takes parameters, and each only allows an array to be modified by a single element at a time. Let's take a look: ```js let greetings = ['whats up?', 'hello', 'see ya!']; greetings.pop(); // now equals ['whats up?', 'hello'] greetings.shift(); // now equals ['hello'] ``` We can also return the value of the removed element with either method like this: ```js let popped = greetings.pop(); // returns 'hello' // greetings now equals [] ``` # --instructions-- We have defined a function, `popShift`, which takes an array as an argument and returns a new array. Modify the function, using `pop()` and `shift()`, to remove the first and last elements of the argument array, and assign the removed elements to their corresponding variables, so that the returned array contains their values. # --hints-- `popShift(["challenge", "is", "not", "complete"])` should return `["challenge", "complete"]` ```js assert.deepEqual(popShift(['challenge', 'is', 'not', 'complete']), [ 'challenge', 'complete' ]); ``` The `popShift` function should utilize the `pop()` method ```js assert.notStrictEqual(popShift.toString().search(/\.pop\(/), -1); ``` The `popShift` function should utilize the `shift()` method ```js assert.notStrictEqual(popShift.toString().search(/\.shift\(/), -1); ``` # --seed-- ## --seed-contents-- ```js function popShift(arr) { let popped; // Change this line let shifted; // Change this line return [shifted, popped]; } console.log(popShift(['challenge', 'is', 'not', 'complete'])); ``` # --solutions-- ```js function popShift(arr) { let popped = arr.pop(); // Change this line let shifted = arr.shift(); // Change this line return [shifted, popped]; } ```