307239: CF1326C. Permutation Partitions

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Description

Permutation Partitions

题意翻译

给定一个长度为 $n$ 的**排列** $\{a_n\}$。要求将这个序列分成互不相交的 $k$ 段。记第 $p$ 段的左端点和右端点分别为 $l_p,r_p$ 。要求最大化 $\sum_{i=1}^k\max_{j=l_i}^{r_i}\{a_j\}$。 输出**最大化的值**和**可以最大化该值的方案数**。方案数对 $998,244,353$ 取模。

题目描述

You are given a permutation $ p_1, p_2, \ldots, p_n $ of integers from $ 1 $ to $ n $ and an integer $ k $ , such that $ 1 \leq k \leq n $ . A permutation means that every number from $ 1 $ to $ n $ is contained in $ p $ exactly once. Let's consider all partitions of this permutation into $ k $ disjoint segments. Formally, a partition is a set of segments $ \{[l_1, r_1], [l_2, r_2], \ldots, [l_k, r_k]\} $ , such that: - $ 1 \leq l_i \leq r_i \leq n $ for all $ 1 \leq i \leq k $ ; - For all $ 1 \leq j \leq n $ there exists exactly one segment $ [l_i, r_i] $ , such that $ l_i \leq j \leq r_i $ . Two partitions are different if there exists a segment that lies in one partition but not the other. Let's calculate the partition value, defined as $ \sum\limits_{i=1}^{k} {\max\limits_{l_i \leq j \leq r_i} {p_j}} $ , for all possible partitions of the permutation into $ k $ disjoint segments. Find the maximum possible partition value over all such partitions, and the number of partitions with this value. As the second value can be very large, you should find its remainder when divided by $ 998\,244\,353 $ .

输入输出格式

输入格式


The first line contains two integers, $ n $ and $ k $ ( $ 1 \leq k \leq n \leq 200\,000 $ ) — the size of the given permutation and the number of segments in a partition. The second line contains $ n $ different integers $ p_1, p_2, \ldots, p_n $ ( $ 1 \leq p_i \leq n $ ) — the given permutation.

输出格式


Print two integers — the maximum possible partition value over all partitions of the permutation into $ k $ disjoint segments and the number of such partitions for which the partition value is equal to the maximum possible value, modulo $ 998\,244\,353 $ . Please note that you should only find the second value modulo $ 998\,244\,353 $ .

输入输出样例

输入样例 #1

3 2
2 1 3

输出样例 #1

5 2

输入样例 #2

5 5
2 1 5 3 4

输出样例 #2

15 1

输入样例 #3

7 3
2 7 3 1 5 4 6

输出样例 #3

18 6

说明

In the first test, for $ k = 2 $ , there exists only two valid partitions: $ \{[1, 1], [2, 3]\} $ and $ \{[1, 2], [3, 3]\} $ . For each partition, the partition value is equal to $ 2 + 3 = 5 $ . So, the maximum possible value is $ 5 $ and the number of partitions is $ 2 $ . In the third test, for $ k = 3 $ , the partitions with the maximum possible partition value are $ \{[1, 2], [3, 5], [6, 7]\} $ , $ \{[1, 3], [4, 5], [6, 7]\} $ , $ \{[1, 4], [5, 5], [6, 7]\} $ , $ \{[1, 2], [3, 6], [7, 7]\} $ , $ \{[1, 3], [4, 6], [7, 7]\} $ , $ \{[1, 4], [5, 6], [7, 7]\} $ . For all of them, the partition value is equal to $ 7 + 5 + 6 = 18 $ . The partition $ \{[1, 2], [3, 4], [5, 7]\} $ , however, has the partition value $ 7 + 3 + 6 = 16 $ . This is not the maximum possible value, so we don't count it.

Input

题意翻译

给定一个长度为 $n$ 的**排列** $\{a_n\}$。要求将这个序列分成互不相交的 $k$ 段。记第 $p$ 段的左端点和右端点分别为 $l_p,r_p$ 。要求最大化 $\sum_{i=1}^k\max_{j=l_i}^{r_i}\{a_j\}$。 输出**最大化的值**和**可以最大化该值的方案数**。方案数对 $998,244,353$ 取模。

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