Find All Duplicates in an Array

You are given an array of n integers where each integer is in the range \(1 \leq a_i \leq n\). Your task is to find all the duplicate numbers in the array without using extra space, aside from the output list. You may modify the array in-place.

If duplicates exist, print them in ascending order, separated by a single space. Otherwise, output -1.

inputFormat

The first line contains a single integer n, the number of elements in the array. The second line contains n space-separated integers representing the array.

outputFormat

Output the duplicate numbers in increasing order, separated by a space. If there are no duplicates, output -1.

8
4 3 2 7 8 2 3 1

2 3