Circular sorting algorithm

Circular sorting
Pre-requisite : elements of the array should be between 1 to length of the array
In Circular Sorting elements are placed at their natural indexs
Example:if the array is [5,4,2,1,3] => [1,2,3,4,5]

import java.util.*;

public class Main {
    public static void main(String[] args) {
      int arr[] = {5,4,2,1,3};
      findDuplicates(arr);
      for(int i =0;i<arr.length;i++){
        System.out.println(arr[i]);
      }
  }
  public static void findDuplicates(int[] nums){
        int i =0,n  = nums.length;
        while(i<n){
            int j = nums[i]-1;
            if(nums[i]!=nums[j]){
                swap(nums,i,j);
            }
            else i++;
        }

    }
    public static void swap(int[] nums,int i ,int j){
        int temp = nums[i];
        nums[i] = nums[j];
        nums[j] = temp;
    }
}

Usage:

• Its useful in identifying duplicates in the array

• It can also be used to find missing elements in the array

Example : Finding missing element in the array of length n where the elements of the array are in the range 0<=element<=n

class Solution {
    public int missingNumber(int[] nums) {
        int i =0,n = nums.length;
        // circular sorting
        while(i<n){
            int  j = nums[i]-1;
            if(j<0) {i++ ; continue;}
            else if(nums[i]!=nums[j]) swap(nums,i,j);
            else i++;
        }
        int missing = 0;
        for(int k = 0;k<nums.length;k++){
            if(k!=nums[k]-1){ missing = k+1; break;}
        }
        return missing;

    }
    public void swap(int[] nums,int i,int j){
        int temp  = nums[i];
        nums[i] = nums[j];
        nums[j] = temp;
    }
}