 ###### STATUS
• Solved
• Unsolved

Find duplicates in an array
Easy Accuracy: 20.69% Submissions: 100k+ Points: 2

Given an array a[] of size N which contains elements from 0 to N-1, you need to find all the elements occurring more than once in the given array.

Example 1:

Input:
N = 4
a[] = {0,3,1,2}
Output: -1
Explanation: N=4 and all elements from 0
to (N-1 = 3) are present in the given
array. Therefore output is -1.


Example 2:

Input:
N = 5
a[] = {2,3,1,2,3}
Output: 2 3
Explanation: 2 and 3 occur more than once
in the given array.

Complete the function duplicates() which takes array a[] and n as input as parameters and returns a list of elements that occur more than once in the given array in sorted manner. If no such element is found return -1.

Expected Time Complexity: O(n).
Expected Auxiliary Space: O(n).
Note : The extra space is only for the array to be returned.
Try and perform all operation withing the provided array.

Constraints:
1 <= N <= 105
0 <= A[i] <= N-1, for each valid i

We are replacing the old Disqus forum with the new Discussions section given below.

### Editorial

We strongly recommend solving this problem on your own before viewing its editorial. Do you still want to view the editorial?

#### My Submissions:  