Selection Sorting in Java Program with Example

How does Selection Sort work?

Selection Sort implements a simple sorting algorithm as follows:

• Algorithm repeatedly searches for the lowest element.
• Swap current element with an element having the lowest value
• With every iteration/pass of selection sort, elements are swapped.

Java Program to implement Selection Sort

package com.guru99;
 
public class SelectionSortAlgo {
 
 
 
 public static void main(String a[])
 {  
  int[] myArray = {860,8,200,9}; 
  
  System.out.println("------Before Selection Sort-----");
 
  printArray(myArray);
 
 
  selection(myArray);//sorting array using selection sort  
 
  System.out.println("-----After Selection Sort-----");  
 
  printArray(myArray); 
 } 
 
  public static void selection(int[] array)
 {  
  for (int i = 0; i < array.length - 1; i++)  
  {  System.out.println("Sort Pass Number "+(i+1));
   int index = i;  
   for (int j = i + 1; j < array.length; j++)
   {   
       System.out.println("Comparing "+ array[index]  + " and " + array[j]);  
    if (array[j] < array[index]){ 
    System.out.println(array[index]  + " is greater than " + array[j] );
     index = j;
    
    
    }  
   }  
 
   int smallerNumber = array[index];   
   array[index] = array[i];  
   array[i] = smallerNumber;  
   System.out.println("Swapping Elements: New Array After Swap");
   printArray(array);
  }  
 }  
 static void printArray(int[] array){
     
     for(int i=0; i < array.length; i++)
  {  
   System.out.print(array[i] + " ");  
  } 
     System.out.println();     
 } 
}

Output:

------Before Selection Sort-----
860 8 200 9 
Sort Pass Number 1
Comparing 860 and 8
860 is greater than 8
Comparing 8 and 200
Comparing 8 and 9
Swapping Elements: New Array After Swap
8 860 200 9 
Sort Pass Number 2
Comparing 860 and 200
860 is greater than 200
Comparing 200 and 9
200 is greater than 9
Swapping Elements: New Array After Swap
8 9 200 860 
Sort Pass Number 3
Comparing 200 and 860
Swapping Elements: New Array After Swap
8 9 200 860 
-----After Selection Sort-----
8 9 200 860