Three-Number Sum or Triplet Sum

Python

Step 1: Thought Process / Set up

Is the array sorted? If not, I will sort the array.

With sorted arrays, I like to utilize pointers

Loop through the array with a for loop

Move pointers using if statements inside the loop

Step: 2: Function Set Up

def triplet(array, sum);
  array.sort()
  three_sum = []
  for :
    if
    elif
  return three_sum

Here is the basic outline of the problem we will solve. We define a function with parameters of an array and sum. I use the basic sorting method to sort the array. I set up an empty list that we will add our three number sum to.

Now that I have the skeleton of the problem, we can start filling out the rest.

for i in range(len(array)-2):

Because we are looking for a three number sum, we will loop through the array and stop before the last two elements.