import java.util.ArrayList;

import java.util.Arrays;

public class DuplicateNumber {

public static void main(String[] args) {

int[] nums = {3,1,3,4,2};

System.out.println(Arrays.toString(findRepeatedNumbers(nums)));

}

static int[] findRepeatedNumbers(int[] nums) {

int i = 0 ;

while (i<nums.length){

int correctIndex = nums[i]-1;

if(nums[correctIndex] != nums[i]){

swap(nums, i, correctIndex);

}else {

i++;

}

}

for (int j = 0; j < nums.length; j++) {

if(nums[j]-1!=j){

return new int[] {nums[j],j+1};

}

}

return new int[]{0,0};

}

static void swap(int[] nums ,int start, int end){

int temp = nums[start];

nums[start] = nums[end];

nums[end] = temp;

}

}