Greatest Common Increasing Subsequence

문제

You are given two sequences of integer numbers. Write a program to determine their common increasing subsequence of maximal possible length.

Sequence S₁, S₂, ..., S_n of length N is called an increasing subsequence of a sequence A₁, A₂, ..., A_M of length M if there exist 1 ≤ i₁ < i₂ < ... < i_N such that  S_j = A_ij for all 1 ≤ j ≤ N, and S_j < S_j+1 for all 1 ≤ j<N.

입력

Each sequence is described with M — its length (1 ≤ M ≤ 500) and M integer numbers A_i (-2³¹ ≤ A_i < 2³¹) — the sequence itself.

출력

On the first line of the output file print L — the length of the greatest common increasing subsequence of both sequences. On the second line print the subsequence itself. If there are several possible answers, output any of them.