min number of swaps required to sort an array code example

Example: minimum swaps to sort an array

import java.io.*;
import java.math.*;
import java.util.*;

public class Swap {
	static int minimumSwaps(int[] arr) {
		int swap=0;
		boolean visited[]=new boolean[arr.length];

		for(int i=0;i<arr.length;i++){
			int j=i,cycle=0;

			while(!visited[j]){
				visited[j]=true;
				j=arr[j]-1;
				cycle++;
			}
			
			if(cycle!=0)
				swap+=cycle-1;
		}
		return swap;
	}

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();
		int[] arr = new int[n];
		
		for (int i = 0; i < n; i++) {
			arr[i] = scanner.nextInt();
		}
		
		int res = minimumSwaps(arr);
		System.out.println(res);
		scanner.close();
	}
}

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Java Example