The
algorithm divides the input list into two parts:

**1.**The sublist of items already sorted, which is built up from left to right at the front (left) of the list, and

**2.**The sublist of items remaining to be sorted that occupy the rest of the list.

Initially,
the sorted sublist is empty and the unsorted sublist is the entire input list.
The algorithm proceeds by finding the smallest (or largest, depending on
sorting order) element in the unsorted sublist, exchanging (swapping) it with
the leftmost unsorted element (putting it in sorted order), and moving the
sublist boundaries one element to the right.

**Example:**

54 35
22 32 21 // this is the initial, starting state of the array

**21**35 22 32 54 // sorted sublist = {21}

**21 22**35 32 54 // sorted sublist = {21, 22}

**21 22 32**35 54 // sorted sublist = {21, 22, 32}

**21 22 32 35**54 // sorted sublist = {21, 22, 32, 35}

**21 22 32 35 54**// sorted sublist = {21, 22, 32, 35, 54}

**Complexity:**

Best
Case : O(n^2)

Average
Case :
O(n^2)

Worst
Case : O(n^2)

import
java.util.Scanner;

public class
SelectionSort {

public static int[] sort(int[] arr) {

// outer loop to
maintain the index of sorted array.

for (int i = 0; i < arr.length - 1; i++) {

int index = i;

// inner loop is
searching in unsorted list.

for (int j = i + 1; j <
arr.length; j++) {

// check for
smallest number’s index.

if (arr[j] <
arr[index]) {

index
= j;

}

}

// swap with left
most unsorted index.

int smallerNumber =
arr[index];

arr[index] =
arr[i];

arr[i] =
smallerNumber;

}

return arr;

}

public static void main(String...args)
{

Scanner scan = new Scanner(System.

*in*);
System.

*out*.println("Enter the no. of elements:");
int size =
scan.nextInt();

int[] array = new int[size];

for(int i =
0;i<size;i++) {

array[i] =
scan.nextInt();

}

int[] sortedArray =

*sort*(array);
for(int e : sortedArray){

System.

*out*.print(e+" ");
}

}

}

**Output:**

Enter the no. of elements:

5

54 35 22 32 21

21 22 32 35 54

**References:**

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