Bubble Sort

// package whatever; // don't place package name!

import java.io.*;
/**
 *  Quadratic Sorts
 *
 *
 *  Problem 3: Bubble Sort
 *
 *  Prompt:    Given an unsorted array of integers, return the array
 *             sorted using bubble sort.
 *
 *  Input:     input {Array}
 *  Output:    {Array}
 *
 *  Example:   [3,9,1,4,7] --> [1,3,4,7,9]
 */

import java.util.*;

class BasicSort {

    public static void main (String[] args) {
    int[] arr = {0};
        System.out.println("output" + Arrays.toString(bubble(arr)));
    }
    public static int[] bubble(int[] input) {
      int index = 0;
      int j = 0;
      int temp = 0;
      int len = input.length;
      boolean swappedFlag;
      for(index = 0; index < len -1; index++){
        swappedFlag = false;
        System.out.println("index: " + index);
        // j resets to first element after every pass
        for(j = 0; j < len -1 -index; j++){
          System.out.println("j : " + j);
          if(input[j] > input[j+1]){
            temp = input[j];
            input[j] = input[j+1];
            input[j+1] = temp;
            swappedFlag = true;
          }
        }
        //if  now swap made, break from the loop
        if(swappedFlag == false){
          //no swaps made in the last pass
          //therefore elements are sorted, break
          break;
        }
      }
    return input;
    }
}