結果

問題 No.931 Multiplicative Convolution
コンテスト
ユーザー lam6er
提出日時 2025-04-15 23:18:21
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 321 ms / 2,000 ms
コード長 2,936 bytes
コンパイル時間 162 ms
コンパイル使用メモリ 81,652 KB
実行使用メモリ 129,760 KB
最終ジャッジ日時 2025-04-15 23:19:43
合計ジャッジ時間 4,568 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge3
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 * 3
other AC * 14
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
root = 3

def factor(n):
    factors = {}
    while n % 2 == 0:
        factors[2] = factors.get(2, 0) + 1
        n = n // 2
    i = 3
    while i * i <= n:
        while n % i == 0:
            factors[i] = factors.get(i, 0) + 1
            n = n // i
        i += 2
    if n > 1:
        factors[n] = 1
    return factors

def find_primitive_root(p):
    if p == 2:
        return 1
    phi = p - 1
    factors = factor(phi)
    for g in range(2, p):
        flag = True
        for q in factors:
            if pow(g, phi // q, p) == 1:
                flag = False
                break
        if flag:
            return g
    return -1

def ntt(a, invert=False):
    n = len(a)
    j = 0
    for i in range(1, n):
        bit = n >> 1
        while j >= bit:
            j -= bit
            bit >>= 1
        j += bit
        if i < j:
            a[i], a[j] = a[j], a[i]
    length = 2
    while length <= n:
        half = length // 2
        step = pow(root, (mod - 1) // length, mod)
        if invert:
            step = pow(step, mod - 2, mod)
        for i in range(0, n, length):
            w = 1
            for j in range(i, i + half):
                u = a[j]
                v = a[j + half] * w % mod
                a[j] = (u + v) % mod
                a[j + half] = (u - v) % mod
                w = w * step % mod
        length <<= 1
    if invert:
        inv_n = pow(n, mod - 2, mod)
        for i in range(n):
            a[i] = a[i] * inv_n % mod
    return a

def convolve(a, b):
    len_a = len(a)
    len_b = len(b)
    max_len = len_a + len_b - 1
    n = 1
    while n < max_len:
        n <<= 1
    fa = a.copy() + [0] * (n - len_a)
    fb = b.copy() + [0] * (n - len_b)
    fa = ntt(fa)
    fb = ntt(fb)
    for i in range(n):
        fa[i] = fa[i] * fb[i] % mod
    fa = ntt(fa, invert=True)
    return fa[:max_len]

def main():
    input = sys.stdin.read().split()
    ptr = 0
    P = int(input[ptr])
    ptr += 1
    A = list(map(int, input[ptr:ptr + P-1]))
    ptr += P-1
    B = list(map(int, input[ptr:ptr + P-1]))
    ptr += P-1
    
    if P == 2:
        c = (A[0] * B[0]) % mod
        print(c)
        return
    
    g = find_primitive_root(P)
    exp_table = [pow(g, m, P) for m in range(P-1)]
    log_table = [0] * (P)
    for m in range(P-1):
        log_table[exp_table[m]] = m
    
    a = [0] * (P-1)
    b = [0] * (P-1)
    for m in range(P-1):
        i = exp_table[m]
        a[m] = A[i-1]
        b[m] = B[i-1]
    
    linear_conv = convolve(a, b)
    N = P-1
    cyclic_conv = [0] * N
    for m in range(N):
        cyclic_conv[m] = linear_conv[m]
        if m + N < len(linear_conv):
            cyclic_conv[m] = (cyclic_conv[m] + linear_conv[m + N]) % mod
    
    C = [0] * (P-1)
    for k in range(1, P):
        m = log_table[k]
        C[k-1] = cyclic_conv[m] % mod
    
    print(' '.join(map(str, C)))

if __name__ == '__main__':
    main()
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