freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../intermediate-algorithm-scri.../seek-and-destroy.english.md

2.6 KiB

id title isRequired challengeType forumTopicId
a39963a4c10bc8b4d4f06d7e Seek and Destroy true 5 16046

Description

You will be provided with an initial array (the first argument in the destroyer function), followed by one or more arguments. Remove all elements from the initial array that are of the same value as these arguments. Note
You have to use the arguments object. Remember to use Read-Search-Ask if you get stuck. Write your own code.

Instructions

Tests

tests:
  - text: <code>destroyer([1, 2, 3, 1, 2, 3], 2, 3)</code> should return <code>[1, 1]</code>.
    testString: assert.deepEqual(destroyer([1, 2, 3, 1, 2, 3], 2, 3), [1, 1]);
  - text: <code>destroyer([1, 2, 3, 5, 1, 2, 3], 2, 3)</code> should return <code>[1, 5, 1]</code>.
    testString: assert.deepEqual(destroyer([1, 2, 3, 5, 1, 2, 3], 2, 3), [1, 5, 1]);
  - text: <code>destroyer([3, 5, 1, 2, 2], 2, 3, 5)</code> should return <code>[1]</code>.
    testString: assert.deepEqual(destroyer([3, 5, 1, 2, 2], 2, 3, 5), [1]);
  - text: <code>destroyer([2, 3, 2, 3], 2, 3)</code> should return <code>[]</code>.
    testString: assert.deepEqual(destroyer([2, 3, 2, 3], 2, 3), []);
  - text: <code>destroyer(["tree", "hamburger", 53], "tree", 53)</code> should return <code>["hamburger"]</code>.
    testString: assert.deepEqual(destroyer(["tree", "hamburger", 53], "tree", 53), ["hamburger"]);
  - text: <code>destroyer(["possum", "trollo", 12, "safari", "hotdog", 92, 65, "grandma", "bugati", "trojan", "yacht"], "yacht", "possum", "trollo", "safari", "hotdog", "grandma", "bugati", "trojan")</code> should return <code>[12,92,65]</code>.
    testString: assert.deepEqual(destroyer(["possum", "trollo", 12, "safari", "hotdog", 92, 65, "grandma", "bugati", "trojan", "yacht"], "yacht", "possum", "trollo", "safari", "hotdog", "grandma", "bugati", "trojan"), [12,92,65]);

Challenge Seed

function destroyer(arr) {
  // Remove all the values
  return arr;
}

destroyer([1, 2, 3, 1, 2, 3], 2, 3);

Solution

function destroyer(arr) {
  var hash = Object.create(null);
  [].slice.call(arguments, 1).forEach(function(e) {
    hash[e] = true;
  });
  // Remove all the values
  return arr.filter(function(e) { return !(e in hash);});
}

destroyer([1, 2, 3, 1, 2, 3], 2, 3);