#585186 (C++17) No.1299 Random Array Score

• 問題: No.1299 Random Array Score
• ユーザー: chocopuu
• 提出日時: 2020-11-27 21:38:09
• 言語: C++17 (gcc 13.2.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 83 ms / 2,000 ms
• コード長: 4,959 bytes
• コンパイル時間: 2,690 ms
• コンパイル使用メモリ: 210,524 KB
• 実行使用メモリ: 4,760 KB
• 最終ジャッジ日時: 2023-10-01 05:04:51
• 合計ジャッジ時間: 5,515 ms
• ジャッジサーバーID （参考情報）: judge13 / judge15

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 4,380 KB
testcase_01	AC	2 ms; 4,380 KB
testcase_02	AC	1 ms; 4,376 KB
testcase_03	AC	76 ms; 4,752 KB
testcase_04	AC	74 ms; 4,636 KB
testcase_05	AC	58 ms; 4,380 KB
testcase_06	AC	51 ms; 4,376 KB
testcase_07	AC	53 ms; 4,380 KB
testcase_08	AC	73 ms; 4,760 KB
testcase_09	AC	4 ms; 4,376 KB
testcase_10	AC	30 ms; 4,376 KB
testcase_11	AC	9 ms; 4,376 KB
testcase_12	AC	48 ms; 4,380 KB
testcase_13	AC	72 ms; 4,736 KB
testcase_14	AC	50 ms; 4,380 KB
testcase_15	AC	51 ms; 4,376 KB
testcase_16	AC	51 ms; 4,380 KB
testcase_17	AC	11 ms; 4,380 KB
testcase_18	AC	33 ms; 4,380 KB
testcase_19	AC	39 ms; 4,380 KB
testcase_20	AC	21 ms; 4,380 KB
testcase_21	AC	3 ms; 4,376 KB
testcase_22	AC	13 ms; 4,380 KB
testcase_23	AC	51 ms; 4,380 KB
testcase_24	AC	57 ms; 4,380 KB
testcase_25	AC	50 ms; 4,376 KB
testcase_26	AC	3 ms; 4,380 KB
testcase_27	AC	14 ms; 4,380 KB
testcase_28	AC	10 ms; 4,380 KB
testcase_29	AC	17 ms; 4,380 KB
testcase_30	AC	48 ms; 4,380 KB
testcase_31	AC	18 ms; 4,380 KB
testcase_32	AC	72 ms; 4,680 KB
testcase_33	AC	83 ms; 4,640 KB
testcase_34	AC	30 ms; 4,552 KB
testcase_35	AC	82 ms; 4,640 KB
testcase_36	AC	30 ms; 4,632 KB

ソースコード

#include "bits/stdc++.h"
using namespace std;
//#include "atcoder/all"
//using namespace atcoder;
#define int long long
#define REP(i, n) for (int i = 0; i < (int)n; ++i)
#define RREP(i, n) for (int i = (int)n - 1; i >= 0; --i)
#define FOR(i, s, n) for (int i = s; i < (int)n; ++i)
#define RFOR(i, s, n) for (int i = (int)n - 1; i >= s; --i)
#define ALL(a) a.begin(), a.end()
#define IN(a, x, b) (a <= x && x < b)
template<class T>istream&operator >>(istream&is,vector<T>&vec){for(T&x:vec)is>>x;return is;}
template<class T>inline void out(T t){cout << t << "\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout << t << " ";out(ts...);}
template<class T>inline bool CHMIN(T&a,T b){if(a > b){a = b;return true;}return false;}
template<class T>inline bool CHMAX(T&a,T b){if(a < b){a = b;return true;}return false;}
constexpr int INF = 1e18;

template<int MOD> struct Fp {
	long long val;
	constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
		if (val < 0) val += MOD;
	}
	constexpr int getmod() { return MOD; }
	constexpr Fp operator - () const noexcept {
		return val ? MOD - val : 0;
	}
	constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; }
	constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; }
	constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; }
	constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; }
	constexpr Fp& operator += (const Fp& r) noexcept {
		val += r.val;
		if (val >= MOD) val -= MOD;
		return *this;
	}
	constexpr Fp& operator -= (const Fp& r) noexcept {
		val -= r.val;
		if (val < 0) val += MOD;
		return *this;
	}
	constexpr Fp& operator *= (const Fp& r) noexcept {
		val = val * r.val % MOD;
		return *this;
	}
	constexpr Fp& operator /= (const Fp& r) noexcept {
		long long a = r.val, b = MOD, u = 1, v = 0;
		while (b) {
			long long t = a / b;
			a -= t * b; swap(a, b);
			u -= t * v; swap(u, v);
		}
		val = val * u % MOD;
		if (val < 0) val += MOD;
		return *this;
	}
	constexpr bool operator == (const Fp& r) const noexcept {
		return this->val == r.val;
	}
	constexpr bool operator != (const Fp& r) const noexcept {
		return this->val != r.val;
	}
	friend constexpr ostream& operator << (ostream &os, const Fp<MOD>& x) noexcept {
		return os << x.val;
	}
	friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
		if (n == 0) return 1;
		auto t = modpow(a, n / 2);
		t = t * t;
		if (n & 1) t = t * a;
		return t;
	}
};
 

template<class T> struct BiCoef {
	vector<T> fact_, inv_, finv_;
	constexpr BiCoef() {}
	constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
		init(n);
	}
	constexpr void init(int n) noexcept {
		fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
		int MOD = fact_[0].getmod();
		for(int i = 2; i < n; i++){
			fact_[i] = fact_[i-1] * i;
			inv_[i] = -inv_[MOD%i] * (MOD/i);
			finv_[i] = finv_[i-1] * inv_[i];
		}
	}
	constexpr T com(int n, int k) const noexcept {
		if (n < k || n < 0 || k < 0) return 0;
		return fact_[n] * finv_[k] * finv_[n-k];
	}
	constexpr T P(int n, int k) const noexcept {
		if (n < k || n < 0 || k < 0) return 0;
		return fact_[n] * finv_[n-k];
	}
	constexpr T fact(int n) const noexcept {
		if (n < 0) return 0;
		return fact_[n];
	}
	constexpr T inv(int n) const noexcept {
		if (n < 0) return 0;
		return inv_[n];
	}
	constexpr T finv(int n) const noexcept {
		if (n < 0) return 0;
		return finv_[n];
	}
};
 
// const int MOD = 1000000007;
const int MOD = 998244353;
using mint = Fp<MOD>;
BiCoef<mint> bc;
// bc.init(500050);

// a^b
long long modpow(long long a, long long n, long long mod) {
	long long res = 1;
	while (n > 0) {
		if (n & 1) res = res * a % mod;
		a = a * a % mod;
		n >>= 1;
	}
	return res;
}

// a^-1
long long modinv(long long a, long long m) {
	long long b = m, u = 1, v = 0;
	while (b) {
		long long t = a / b;
		a -= t * b; swap(a, b);
		u -= t * v; swap(u, v);
	}
	u %= m;
	if (u < 0) u += m;
	return u;
}

// a^x ≡ b (mod. m) となる最小の正の整数 x を求める
long long modlog(long long a, long long b, int m) {
	a %= m, b %= m;

	// calc sqrt{M}
	long long lo = -1, hi = m;
	while (hi - lo > 1) {
		long long mid = (lo + hi) / 2;
		if (mid * mid >= m) hi = mid;
		else lo = mid;
	}
	long long sqrtM = hi;

	// {a^0, a^1, a^2, ..., a^sqrt(m)} 
	map<long long, long long> apow;
	long long amari = 1;
	for (long long r = 0; r < sqrtM; ++r) {
		if (!apow.count(amari)) apow[amari] = r;
		(amari *= a) %= m;
	}

	// check each A^p
	long long A = modpow(modinv(a, m), sqrtM, m);
	amari = b;
	for (long long q = 0; q < sqrtM; ++q) {
		if (apow.count(amari)) {
			long long res = q * sqrtM + apow[amari];
			if (res > 0) return res;
		}
		(amari *= A) %= m;
	}

	// no solutions
	return -1;
}

signed main(){
	int N, K;
	cin >> N >> K;
	vector<int> a(N);
	cin >> a;
	mint m = accumulate(ALL(a), mint(0)) / mint(N);
	m *= modpow(mint(2), K);
	//out(m);
	out(m * N);
}