Javascript Algorithm:Bubble Sort(FreeCodeCamp)

Implement Bubble Sort:

This is the first of several challenges on sorting

algorithms. Given an array of unsorted items, we want to be able to return a

sorted array. We will see several different methods to do this and learn some

tradeoffs between these different approaches. While most modern languages have

built-in sorting methods for operations like this, it is still important to

understand some of the common basic approaches and learn how they can be

implemented.

Here we will see bubble sort. The bubble sort method starts at the beginning of

an unsorted array and 'bubbles up' unsorted values towards the end, iterating

through the array until it is completely sorted. It does this by comparing

adjacent items and swapping them if they are out of order. The method continues

looping through the array until no swaps occur at which point the array is

sorted.

This method requires multiple iterations through the array and for average and

worst cases has quadratic time complexity. While simple, it is usually

impractical in most situations.

Instructions: Write a function bubbleSort which takes an array of integers as

input and returns an array of these integers in sorted order from least to

greatest.

Test Cases:

1) bubbleSort should be a function.

2) bubbleSort should return a sorted array (least to greatest).

3) bubbleSort([1,4,2,8,345,123,43,32,5643,63,123,43,2,55,1,234,92])

should return an array that is unchanged except for order.

4) bubbleSort should not use the built-in .sort() method.

Solution:

function bubbleSort(array) {

for (let i = 0; i < array.length-1; i++){

for (let j = i+1; j < array.length; j++){

if(array[i]> array[j]){

[array[i],array[j]] = [array[j],array[i]]

}

}

}

return array;

}

let result = bubbleSort([

1, 4, 2, 8, 345, 123, 43, 32, 5643, 63, 123, 43, 2, 55, 1, 234, 92,

]);

console.log(result)

Here the smallest element has "bubbled up" to the top of the array.