Sorting Algorithms (Java Bubble Sort Example)

    /*
    Java Bubble Sort Example
    This Java bubble sort example shows how to sort an array of int using bubble
    sort algorithm. Bubble sort is the simplest sorting algorithm.
    */
    
    public class BubbleSort {
    
    public static void main(String[] args) {
    
    //create an int array we want to sort using bubble sort algorithm
    int intArray[] = new int[]{5,90,35,45,150,3};
    
    //print array before sorting using bubble sort algorithm
    System.out.println("Array Before Bubble Sort");
    for(int i=0; i < intArray.length; i++){
    System.out.print(intArray[i] + " ");
    }
    
    //sort an array using bubble sort algorithm
    bubbleSort(intArray);
    
    System.out.println("");
    
    //print array after sorting using bubble sort algorithm
    System.out.println("Array After Bubble Sort");
    for(int i=0; i < intArray.length; i++){
    System.out.print(intArray[i] + " ");
    }
    
    }
    
    private static void bubbleSort(int[] intArray) {
    
    /*
    * In bubble sort, we basically traverse the array from first
    * to array_length - 1 position and compare the element with the next one.
    * Element is swapped with the next element if the next element is greater.
    *
    * Bubble sort steps are as follows.
    *
    * 1. Compare array[0] & array[1]
    * 2. If array[0] > array [1] swap it.
    * 3. Compare array[1] & array[2]
    * 4. If array[1] > array[2] swap it.
    * ...
    * 5. Compare array[n-1] & array[n]
    * 6. if [n-1] > array[n] then swap it.
    *
    * After this step we will have largest element at the last index.
    *
    * Repeat the same steps for array[1] to array[n-1]
    *
    */
    
    int n = intArray.length;
    int temp = 0;
    
    for(int i=0; i < n; i++){
    for(int j=1; j < (n-i); j++){
    
    if(intArray[j-1] > intArray[j]){
    //swap the elements!
    temp = intArray[j-1];
    intArray[j-1] = intArray[j];
    intArray[j] = temp;
    }
    
    }
    }
    
    }
    }
    
    /*
    Output of the Bubble Sort Example would be
    
    Array Before Bubble Sort
    5 90 35 45 150 3
    Array After Bubble Sort
    3 5 35 45 90 150
    
    */