#743. Vawio Sequence
Vawio Sequence
说明
Vawio Sequence is very funny,it is a sequence of integers. It has some interesting properties.
· Vawio is of odd length i.e. L = 2*n + 1.
· The first (n+1) integers of Vawio sequence makes a strictly increasing sequence.
· The last (n+1) integers of Vawio sequence makes a strictly decreasing sequence.
· No two adjacent integers are same in a Vawio sequence.
For example 1, 2, 3, 4, 5, 4, 3, 2, 0 is an Vawio sequence of length 9. But 1, 2, 3, 4, 5, 4, 3, 2, 2 is not a valid Vawio sequence. In this problem, you will be given a sequence of integers. You have to find out the length of the longest Vawio sequence which is a subsequence of the given sequence. Consider, the given sequence as :
1 2 3 2 1 2 3 4 3 2 1 5 4 1 2 3 2 2 1.
Here the longest Wavio sequence is : 1 2 3 4 5 4 3 2 1. So, the output will be 9.
输入格式
The input file contains less than 75 test cases. The description of each test case is given below: Input is terminated by end of file.Each set starts with a postive integer, N(1<=N<=10000). In next few lines there will be N integers
输出格式
For each set of input print the length of longest Vawio sequence in a line.10
1 2 3 4 5 4 3 2 1 10
19
1 2 3 2 1 2 3 4 3 2 1 5 4 1 2 3 2 2 1
5
1 2 3 4 5
9
9
1