Venzee Hackathon

This purpose of this hackathon is to show off your Javascript skills. For this set of exercises, you are required to implement a set of utility functions using Javascript to manipulate Arrays and Objects. If you are familiar with such libraries as Underscore or Lodash, then this will be very similar to those.

While it will be tempting to read the source code of such libraries and/or copy code from other sources. It's recommended that you try to solve this on your own. Your implementation should be written in pure Javascript without any use of external libraries or helpers. Also you're not allowed to use the builtin functions of javascript that provide the same behavior (i.e. [1,2].map()).

Submission:

• Fork this repositroy.
• Solve each function in a separate branch.
• Submit a Pull Request to your fork for each separate working function described.
• Send your Pull Request to the #code channel on Slack.

What we will look for:

• Working and functional code as described.
• Algorithmic thinking (How you tackled the problem):
  • Number of lines of code.
  • Time complexity.
  • Space complexity.
• Code style and cleanance.

Exercise:

Arrays:

These set of exercises are focused solely on Array manipulations.

Map

Map each element in an array to a new value based on a supplied function. It should return a new array with the mapped values.

function square(n) {
  return n * n;
}
 
map([4, 8], square);
// => [16, 64]

Reduce

Reduces array to a value which is the accumulated result of running each element through a supplied function. It should return a single accumulated value.

function sum(a, b){
	return a + b;
}

reduce([1, 2], sum, 0);
// => 3

Uniq

Returns the unique elements in an array.

uniq([3, 1, 2, 1, 4, 3, 2]);
// => [3, 1, 2, 4]

Objects:

These set of exercises are focused solely on Object manipulations.

Merge

Marge two objects (object1, object2) into a single one, it should be able to traverse the hierarchy of the object and map nested objects:

Properties with same key:

• If the value is a literal or a function: take the value of the second object (object2).
• If the value is an array: merge each element from the array with the element from the other array.
• If the value is an object: merge them following the same rules as above.

var object = {
  'a': 1,
  'b': [1, 2],
  'c': {
    'd': 'foo',
    'e': 'hello'
   }
};

var other = {
  'a': 2,
  'b': [3, 4],
  'c': {
    'd': 'bar',
    'f': 'world'
   }
};
 
var other = {
  'a': [{ 'c': 3 }, { 'e': 5 }]
};
 
merge(object, other);
// => {
  'a': 2,
  'b': [[1, 3], [2, 4]],
  'c': {
    'd': 'bar',
    'e': 'hello',
    'f': 'world'
   }
};