#P2127. Greatest Common Increasing Subsequence
Greatest Common Increasing Subsequence
Description
You are given two sequences of integer numbers. Write a program to determine their common increasing subsequence of maximal possible length.
Sequence S1 , S2 , . . . , SN of length N is called an increasing subsequence of a sequence A1 , A2 , . . . , AM of length M if there exist 1 <= i1 < i2 < . . . < iN <= M such that Sj = Aij for all 1 <= j <= N , and Sj < Sj+1 for all 1 <= j < N .
Input
Each sequence is described with M --- its length (1 <= M <= 500) and M integer numbers Ai (-231 <= Ai < 231 ) --- the sequence itself.
Output
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.
5
1 4 2 5 -12
4
-12 1 2 4
2
1 4
Source
Northeastern Europe 2003, Northern Subregion