1030: SYH’s Easy Array Problem

SYH has an array a₁~a_n which has n elements. You are asked to find an array b₁~b_n that satisfies the following rules:

1. b₁=0

2. For any pair of (i, j), if a_i=a_j, b_i=b_j. However, if a_i≠a_j, b_i=b_j is also accepted.

3. For any i which 1 ≤ i < n, either b_i=b_i+1 or b_i+1=b_i+1.

    SYH wants to know how many legal b array there are.

The first line conatins an integer T, means the number of test cases. For each test case, the first line contains one integer n. The second line contains n integers a₁ to a_n.
     

For each test case ouput “Case: #x: y” in a single line. x is the test case number (starting from 1), and y is your answer. Notice, the answer may be very big, so please module 998244353 before you output it.

2

5
1 2 1 2 3

4
1 3 3 7

Case #1: 2
Case #2: 4