p5.js | Bubble Sort

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Bubble Sort is the simplest sorting algorithm that works by repeatedly swapping the adjacent elements if they are in the wrong order.

In order to know more about it. Please refer Bubble Sort

Approach:

Create an array of random values and render a bar corresponding to that value in terms of height.
Create a function for bubble sort which compares the adjacent bar in order to swap the bar.
In order to get better visualization, set the color to the bar which is currently being processed (red in example shown below).

Example:

<!DOCTYPE html> 
<html> 
  
<head> 
    <title>Bubble Sort</title> 
      
    <meta charset="UTF-8"> 
  
    <script src= 
"https://cdnjs.cloudflare.com/ajax/libs/p5.js/0.8.0/p5.min.js"
    type="text/javascript"></script> 
      
    <style>  
        body { 
            padding: 0; 
  
        } 
        canvas { 
            vertical-align: top; 
        }  
    </style> 
</head>  
  
<body> 
    <script type="text/javascript"> 
      
        // Set Global Variables  
        let values = []; 
        let w = 20; 
           
        // To store the state of each bar 
        // in order to change the color 
        let states = []; 
           
           
        function setup() { 
              
            // Create Canvas of Size Windows 
            // Width * Windows Height 
            createCanvas(800, 400); 
           
            // Insert Random values in array 
            values = new Array(floor(width/w)); 
           
            for(let i = 0; i < values.length; i++) { 
                values[i] = float(random(height)); 
                states[i] = -1;  
            } 
           
            // Print Unsorted Array 
            print("Unsorted Array:" + values); 
           
            // Call to bubble sort function 
            bubbleSort(values, 0, values.length); 
           
            // Print Sorted Array 
            print("Sorted Array:" + values); 
           
        } 
           
        // Definition of bubble sort 
        async function bubbleSort(arr, start, end) { 
            if(start >= end) { 
                return; 
            } 
            
            for(var i = 0; i < end-1; i++) { 
                for(var j = 0; j < end-i-1; j++) { 
                    if(arr[j] >= arr[j+1]) { 
                        states[j] = 1; 
           
                        // Call to swap function 
                        await swap(arr, j, j+1); 
                        states[j+1] = 0; 
                    } 
                    states[j] = 2; 
                } 
            } 
            return arr; 
        } 
           
        // Definition of draw function 
        function draw() { 
            background(51); 
              
            for(let i = 0; i < values.length; i++) { 
                stroke(0); 
                fill(255); 
                  
                if(states[i] == 0) { 
                    fill(255, 0, 0); 
                } 
                else if (states[i] == 1) { 
                      
                    // Element currently sorting 
                    fill("#58FA82"); 
                } 
                else { 
                    fill(255); 
                } 
                rect(i*w, height - values[i], w, values[i]); 
            } 
        } 
           
        // Definition of swap function 
        async function swap(arr, a, b) { 
             
            await sleep(20); 
            let t = arr[a]; 
            arr[a] = arr[b]; 
            arr[b] = t; 
        } 
           
        // Definition of sleep function 
        function sleep(ms) { 
            return new Promise(resolve => setTimeout(resolve, ms)); 
        } 
    </script> 
</body> 
  
</html>             