Bubble Sort

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

Time complexity :

In Average/Worst Case : it usually takes n number of passes to sort an array and complexity becomes O(n^2)
In Best Case : it takes O(n) time complexity , and it happens only when the array is already sorted.

Bubble Sort Example :

// Java program to implement Bubble Sort 
class BubbleSortPT
{ 
  void bubbleSort(int arr[]) 
  { 
    int n = arr.length; 
    for (int i = 0; i < n-1; i++) 
    for (int j = 0; j < n-i-1; j++) 
    if (arr[j] > arr[j+1]) 
    { 
     // swap arr[j+1] and arr[i] 
     int temp = arr[j]; 
     arr[j] = arr[j+1]; 
     arr[j+1] = temp; 
    } 
  }

  /* Prints the array */
  void printArray(int arr[]) 
  { 
    int n = arr.length; 
    for (int i=0; i<n; ++i) 
    System.out.print(arr[i] + " "); 
    System.out.println(); 
  }

  // Main method to test the above code
  public static void main(String args[]) 
  { 
    BubbleSortPT ob = new BubbleSortPT(); 
    int arr[] = {64, 34, 25, 12, 22, 11, 90}; 

    ob.bubbleSort(arr); 
    System.out.println("Sorted array"); 
    ob.printArray(arr); 
  } 
}

OUTPUT

Sorted array
11 12 22 25 34 64 90 

Summary

In this article we learnt about bubble sort and its time complexities.
Hope you liked it !

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