Unique Maximum Number
Problem
Given an array A. Find the highest unique element in array A. Unique element means that element should present only once in the array.
Input:
First line of input contains N, size of array A. Next line contains N space separated elements of array A.
Output:
Print highest unique number of array A. If there is no any such element present in array then print -1.
Constraints:
1 ≤ N ≤ 106
0 ≤ Ai ≤ 109
Time Limit: 5
Memory Limit: 256
Source Limit:
Explanation
In array A:
9 occur two times. 8 occur two times. 5 occur once hence the answer is 5.
