結果

問題 No.2959 Dolls' Tea Party
ユーザー gew1fw
提出日時 2025-06-12 19:04:23
言語 PyPy3
(7.3.15)
結果
TLE  
実行時間 -
コード長 2,159 bytes
コンパイル時間 221 ms
コンパイル使用メモリ 81,976 KB
実行使用メモリ 60,936 KB
最終ジャッジ日時 2025-06-12 19:04:39
合計ジャッジ時間 6,175 ms
ジャッジサーバーID
(参考情報)
judge2 / judge1
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 4
other AC * 2 TLE * 1 -- * 30
権限があれば一括ダウンロードができます

ソースコード

diff #

import sys
MOD = 998244353

def main():
    N, K = map(int, sys.stdin.readline().split())
    A = list(map(int, sys.stdin.readline().split()))
    
    # Precompute divisors of K
    divisors = []
    for i in range(1, int(K**0.5)+1):
        if K % i == 0:
            divisors.append(i)
            if i != K // i:
                divisors.append(K // i)
    divisors.sort()
    
    # Precompute inv_fact up to 1300
    max_m = 1300
    inv_fact = [1] * (max_m + 1)
    # Precompute factorials modulo MOD
    fact = [1] * (max_m + 1)
    for i in range(1, max_m + 1):
        fact[i] = fact[i-1] * i % MOD
    # Compute inverse factorials using Fermat's little theorem
    inv_fact[max_m] = pow(fact[max_m], MOD-2, MOD)
    for i in range(max_m-1, -1, -1):
        inv_fact[i] = inv_fact[i+1] * (i+1) % MOD
    
    # Precompute Euler's totient function for all divisors of K
    def compute_phi(n):
        result = n
        i = 2
        while i*i <= n:
            if n % i == 0:
                while n % i == 0:
                    n //= i
                result -= result // i
            i += 1
        if n > 1:
            result -= result // n
        return result
    phi = {d: compute_phi(d) for d in divisors}
    
    total = 0
    for d in divisors:
        m = K // d
        if m == 0:
            continue
        
        # Precompute B_i = A_i // d for each doll type
        B = [a // d for a in A]
        
        current_dp = [0] * (m + 1)
        current_dp[0] = 1
        
        for b in B:
            next_dp = [0] * (m + 1)
            for j in range(m + 1):
                if current_dp[j] == 0:
                    continue
                max_c = min(b, m - j)
                for c in range(0, max_c + 1):
                    if j + c > m:
                        continue
                    next_dp[j + c] = (next_dp[j + c] + current_dp[j] * inv_fact[c]) % MOD
            current_dp = next_dp
        
        S = current_dp[m]
        F_d = S * fact[m] % MOD
        
        total = (total + phi[d] * F_d) % MOD
    
    ans = total * pow(K, MOD-2, MOD) % MOD
    print(ans)

if __name__ == '__main__':
    main()
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