limjiechao / array-practice-1

Array practice

Complete the following exercises to improve your understanding of arrays in javascript!

Instructions:

• In main.js, define the functions listed below and test that it works by running it against helper.test(yourFunction(), yourExpectedValue). To run the test, run node main.js in your terminal
• As opposed to manually checking the output every time you run the function, we've written a helper method (helper.test()) to help you check whether your code produces the expected output.
• For each function, add 1-2 more test cases to confirm that your function really works.

Exercises:

1. Write a JavaScript function which accept a number as input and insert dashes (-) between each two even numbers.

• Sample input: 025486
• Sample output: 0-254-8-6

2. Write a Javascript function to find the most frequent item of an array. It should return a string denoting the item and the number of times it occurs in the array.

• Sample input: [3, 'a', 'a', 'a', 2, 3, 'a', 3, 'a', 2, 4, 9, 3];
• Sample output : 'a (5 times)'

3. Write a Javascript function to remove duplicate items from an array (ignore case sensitivity).

• Sample input : [1, 'a', 'A', 'b', 2, 2]
• Sample output: [1, 'a', 'b', 2]

4. Write a Javascript function to compute the union of two arrays.

• Sample input: union([1, 2, 3], [100, 2, 1, 10])
• Sample output: [1, 2, 3, 10, 100]

5. Write a JavaScript function to merge two arrays and removes all duplicates elements.

• Sample input: mergeArray([1, 2, 3], [2, 30, 1])
• Sample output: [3, 2, 30, 1]