Description: 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: a1 < a2 < ... < ai - 1 < ai > ai + 1 > ... > a|a| - 1 > a|a|. 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? Input Format: 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. Output Format: In the first line print the number of cards you can put on the table. In the second line print the resulting stairs. Note: None