Permutation Partitions

2020 VietMX ACM 0

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 $998\,244\,353$.Input

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.Output

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 $998\,244\,353$.Examplesinput

3 2
2 1 3

output

5 2

input

5 5
2 1 5 3 4

output

15 1

input

7 3
2 7 3 1 5 4 6

output

18 6

Note

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.

Solution:

#include <bits/stdc++.h>

using namespace std;

template <typename T>
T inverse(T a, T m) {
T u = 0, v = 1;
while (a != 0) {
T t = m / a;
m -= t * a; swap(a, m);
u -= t * v; swap(u, v);
}
assert(m == 1);
return u;
}

template <typename T>
class Modular {
public:
using Type = typename decay<decltype(T::value)>::type;

constexpr Modular() : value() {}
template <typename U>
Modular(const U& x) {
value = normalize(x);
}

template <typename U>
static Type normalize(const U& x) {
Type v;
if (-mod() <= x && x < mod()) v = static_cast<Type>(x);
else v = static_cast<Type>(x % mod());
if (v < 0) v += mod();
    return v;
  }

  const Type& operator()() const { return value; }
  template <typename U>
explicit operator U() const { return static_cast<U>(value); }
constexpr static Type mod() { return T::value; }

Modular& operator+=(const Modular& other) { if ((value += other.value) >= mod()) value -= mod(); return *this; }
Modular& operator-=(const Modular& other) { if ((value -= other.value) < 0) value += mod(); return *this; }
  template <typename U> Modular& operator+=(const U& other) { return *this += Modular(other); }
template <typename U> Modular& operator-=(const U& other) { return *this -= Modular(other); }
Modular& operator++() { return *this += 1; }
Modular& operator--() { return *this -= 1; }
Modular operator++(int) { Modular result(*this); *this += 1; return result; }
Modular operator--(int) { Modular result(*this); *this -= 1; return result; }
Modular operator-() const { return Modular(-value); }

template <typename U = T>
typename enable_if<is_same<typename Modular<U>::Type, int>::value, Modular>::type& operator*=(const Modular& rhs) {
#ifdef _WIN32
uint64_t x = static_cast<int64_t>(value) * static_cast<int64_t>(rhs.value);
uint32_t xh = static_cast<uint32_t>(x >> 32), xl = static_cast<uint32_t>(x), d, m;
asm(
"divl %4; \n\t"
: "=a" (d), "=d" (m)
: "d" (xh), "a" (xl), "r" (mod())
);
value = m;
#else
value = normalize(static_cast<int64_t>(value) * static_cast<int64_t>(rhs.value));
#endif
return *this;
}
template <typename U = T>
typename enable_if<is_same<typename Modular<U>::Type, int64_t>::value, Modular>::type& operator*=(const Modular& rhs) {
int64_t q = static_cast<int64_t>(static_cast<long double>(value) * rhs.value / mod());
value = normalize(value * rhs.value - q * mod());
return *this;
}
template <typename U = T>
typename enable_if<!is_integral<typename Modular<U>::Type>::value, Modular>::type& operator*=(const Modular& rhs) {
value = normalize(value * rhs.value);
return *this;
}

Modular& operator/=(const Modular& other) { return *this *= Modular(inverse(other.value, mod())); }

template <typename U>
friend const Modular<U>& abs(const Modular<U>& v) { return v; }

template <typename U>
friend bool operator==(const Modular<U>& lhs, const Modular<U>& rhs);

template <typename U>
friend bool operator<(const Modular<U>& lhs, const Modular<U>& rhs);

template <typename U>
friend std::istream& operator>>(std::istream& stream, Modular<U>& number);

private:
Type value;
};

template <typename T> bool operator==(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value == rhs.value; }
template <typename T, typename U> bool operator==(const Modular<T>& lhs, U rhs) { return lhs == Modular<T>(rhs); }
template <typename T, typename U> bool operator==(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) == rhs; }

template <typename T> bool operator!=(const Modular<T>& lhs, const Modular<T>& rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(const Modular<T>& lhs, U rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(U lhs, const Modular<T>& rhs) { return !(lhs == rhs); }

template <typename T> bool operator<(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value < rhs.value; }

template <typename T> Modular<T> operator+(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }

template <typename T> Modular<T> operator-(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }

template <typename T> Modular<T> operator*(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }

template <typename T> Modular<T> operator/(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }

template<typename T, typename U>
Modular<T> power(const Modular<T>& a, const U& b) {
assert(b >= 0);
Modular<T> x = a, res = 1;
U p = b;
while (p > 0) {
if (p & 1) res *= x;
x *= x;
p >>= 1;
}
return res;
}

template <typename T>
bool IsZero(const Modular<T>& number) {
return number() == 0;
}

template <typename T>
string to_string(const Modular<T>& number) {
return to_string(number());
}

template <typename T>
std::ostream& operator<<(std::ostream& stream, const Modular<T>& number) {
return stream << number();
}

template <typename T>
std::istream& operator>>(std::istream& stream, Modular<T>& number) {
typename common_type<typename Modular<T>::Type, int64_t>::type x;
stream >> x;
number.value = Modular<T>::normalize(x);
return stream;
}

/*
using ModType = int;

struct VarMod { static ModType value; };
ModType VarMod::value;
ModType& md = VarMod::value;
using Mint = Modular<VarMod>;
*/

constexpr int md = 998244353;
using Mint = Modular<std::integral_constant<decay<decltype(md)>::type, md>>;

int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, k;
cin >> n >> k;
vector<int> p(n);
for (int i = 0; i < n; i++) {
    cin >> p[i];
--p[i];
}
vector<int> pos;
long long ans = 0;
for (int i = 0; i < n; i++) {
    if (p[i] >= n - k) {
pos.push_back(i);
ans += p[i] + 1;
}
}
Mint ways = 1;
for (int i = 0; i < (int) pos.size() - 1; i++) {
    ways *= pos[i + 1] - pos[i];
  }
  cout << ans << " " << ways << '\n';
  return 0;
}

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