Minimum Swaps - HackerRank You are given an unordered array consisting of consecutive integers [1, 2, 3, ..., n] without any duplicates. You are allowed to swap any two elements. You need to find the minimum number of swaps required to sort the array in ascending order.

minimunSwaps.java

package minimunSwaps;

import java.util.HashMap;
import java.util.Map.Entry;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int[] arr = { 7, 1, 3, 2, 4, 5, 6 };
		System.out.println(minimumSwaps(arr));
	}

	static int minimumSwaps(int[] arr) {

		boolean[] visitedFlag=new boolean[arr.length+1];
		
		int count=0;
		HashMap<Integer, Integer> mapItemIndex=new HashMap<>();
		
		for (int i = 1; i <= arr.length; i++) {
			mapItemIndex.put(i, arr[i-1]);
		}
		
		
		for (int i = 1; i <= mapItemIndex.size(); i++) { // index = i
			int newValue;
			if (!visitedFlag[i]) {
				visitedFlag[i]=true;
				
				if (mapItemIndex.get(i)!=i) {
					int c = mapItemIndex.get(i);
					while (!visitedFlag[c]) {
						visitedFlag[c]=true;
						newValue = mapItemIndex.get(c);
						c=newValue;
						count++;
					}
				}
			
				
			}
		}
		
		
		
		return count;
	}
	

}