# Java Program to Implement Fisher-Yates Algorithm for Array Shuffling

This is java implementation of the Fisher–Yates shuffle (named after Ronald Fisher and Frank Yates)algorithm, also known as the Knuth shuffle (after Donald Knuth), for generating a random permutation of a finite set—in plain terms, for randomly shuffling the set.

Here is the source code of the Java Program to Implement Fisher-Yates Algorithm for Array Shuffling. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.

//This is a sample program to shuffle the elements of an array using Fisher Yates Array Shuffling algorithm
import java.util.Random;
import java.util.Scanner;

public class Fisher_Yates_Array_Shuffling
{
static int[] fisherYatesShuffling(int []arr, int n)
{
int []a = new int[n];
int []ind = new int[n];
for(int i=0; i<n; i++)
ind[i] = 0;
int index;
Random rand = new Random();
for(int i=0; i<n; i++)
{
do
{
index = rand.nextInt(n);
} while(ind[index] != 0);

ind[index] = 1;
a[i] = arr[index];
}
return a;
}

public static void main(String agrs[])
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the array size: ");
int n = sc.nextInt();
System.out.println("Enter the array elements: ");
int []a = new int[n];
int []res = new int[n];
for(int i=0; i<n; i++)
{
a[i] = sc.nextInt();
}
res = fisherYatesShuffling(a, n);
for(int i=0; i<n; i++)
{
System.out.print(res[i]+" ");
}
sc.close();
}
}


Output:

$javac Fisher_Yates_Array_Shuffling.java$ java Fisher_Yates_Array_Shuffling
Enter the array size:
12
Enter the array elements:
1 2 3 4 5 6 7 8 9 10 11 12
The shuffled elements are:
7 10 8 4 9 6 12 3 2 1 5 11