A warehouse inventory scan produces a log of m SKU codes. Every SKU code in the log appears exactly twice, except for exactly two SKU codes, which each appear exactly once (they were scanned before a shelf reshuffle interrupted the second pass).
Given the log, identify those two SKU codes.
Input format
Line 1: an integer m, the number of entries in the log.
Line 2: m space-separated non-negative integers, the scanned SKU codes.
Output format
The two SKU codes that appear exactly once, printed in ascending order, separated by a single space.
Constraints
- 4 ≤ m ≤ 200 (m is guaranteed even: pairs plus exactly two singles)
- 0 ≤ SKU code ≤ 999,999