Two Sum

Given an array of integers nums and an integer target , return indices of the two numbers such that they add up to target .

##For Example
console.log(twoSum([1, 6, 4, 5, 3, 3], 7)); => [ [ 6, 1 ], [ 3, 4 ], [ 3, 4 ] ] console.log(twoSum([40, 11, 19, 17, -12], 28)); => [ [ 17, 11 ], [ -12, 40 ] ]

##

function twoSum(numArray, sum) {
  var pairs = [];
  var hashtable = [];

  for (var i = 0; i < numArray.length; i++) {
    var currNum = numArray[i]; 
    var counterpart = sum - currNum;
    if (hashtable.indexOf(counterpart) !== -1) {
      pairs.push([currNum, counterpart])

    }
    hashtable.push(currNum)
  }
  return pairs;
}

console.log(twoSum([1, 6, 4, 5, 3, 3], 7));
console.log(twoSum([40, 11, 19, 17, -12], 28));

Two Build our two sum algorithm we start by defining a function called twoSum this function will have two arguments an array and a sum
The first thing we want to do to create an an array called pairs. Next we want to create a loop that will iterate in our argument called numArray. We will define the current number by saying var currNum = numArray[i] at position i.

What we want to do is to create a hashtable and create a variable hashtable to store our numbers. We have our current number now we have to define our counterpart by createing variable counterpart that is the sum - currNum;
Now we have to check our hashtable to see if our couterpart exist in it. We create if statement if hashtable indexOf couterpart is true or is different of -1; We push into pairs the currNum and counterpart

Outside of our if statement we need to push into our hashtable by pushing the currNum

In the end we return the pairs.