Sereja loves integer sequences very much. He especially likes stairs.
Sequence a1, a2, ..., a|a| (|a| is the length of the sequence) is stairs if there is such index i (1 ≤ i ≤ |a|), that the following condition is met:
For example, sequences [1, 2, 3, 2] and [4, 2] are stairs and sequence [3, 1, 2] isn't.
Sereja has m cards with numbers. He wants to put some cards on the table in a row to get a stair sequence. What maximum number of cards can he put on the table?
The first line contains integer m (1 ≤ m ≤ 105) — the number of Sereja's cards. The second line contains m integers bi (1 ≤ bi ≤ 5000) — the numbers on the Sereja's cards.
In the first line print the number of cards you can put on the table. In the second line print the resulting stairs.
5
1 2 3 4 5
5
5 4 3 2 1
6
1 1 2 2 3 3
5
1 2 3 2 1