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## Problem Description
Find the number of ways to divide an array a of n integers into any number of disjoint non-empty segments so that, in each segment, there exist at most k distinct integers that appear exactly once.
Since the answer can be large, find it modulo 998 244 353.
Input
The first line contains two space-separated integers n and k (1 ≤ k ≤ n ≤ 10^5) — the number of elements in the array a and the restriction from the statement.
The following line contains n space-separated integers a_1, a_2, …, a_n (1 ≤ a_i ≤ n) — elements of the array a.
Output
The first and only line contains the number of ways to divide an array a modulo 998 244 353.
Examples
Input
3 1
1 1 2
Output
3
Input
5 2
1 1 2 1 3
Output
14
Input
5 5
1 2 3 4 5
Output
16
Note
In the first sample, the three possible divisions are as follows.
* [[1], [1], [2]]
* [[1, 1], [2]]
* [[1, 1, 2]]
Division [[1], [1, 2]] is not possible because two distinct integers appear exactly once in the second segment [1, 2].
## Contest Information
- **Contest ID**: 1129
- **Problem Index**: D
- **Points**: 2250.0
- **Rating**: 2900
- **Tags**: data structures, dp
- **Time Limit**: {'seconds': 3, 'nanos': 0} seconds
- **Memory Limit**: 256000000 bytes
## Task
Solve this competitive programming problem. Provide a complete solution that handles all the given constraints and edge cases. |