結果

問題 No.3478 XOR-Folding Primes
コンテスト
ユーザー まぬお
提出日時 2026-03-31 04:29:26
言語 PyPy3
(7.3.17)
コンパイル:
pypy3 -mpy_compile _filename_
実行:
pypy3 _filename_
結果
AC  
実行時間 2,533 ms / 4,000 ms
コード長 3,063 bytes
記録
記録タグの例:
初AC ショートコード 純ショートコード 純主流ショートコード 最速実行時間
コンパイル時間 129 ms
コンパイル使用メモリ 85,760 KB
実行使用メモリ 273,988 KB
最終ジャッジ日時 2026-03-31 04:29:41
合計ジャッジ時間 13,160 ms
ジャッジサーバーID
(参考情報)
judge1_0 / judge3_0
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 1
other AC * 8
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 #
raw source code

from collections import deque, defaultdict, Counter
from bisect import bisect_left, bisect_right
from itertools import permutations, combinations, groupby
from heapq import heappop, heappush
import math, sys
input = lambda: sys.stdin.readline().rstrip("\r\n")
def printl(li, sep=" "): print(sep.join(map(str, li)))
def yn(flag): print(Yes if flag else No)
_int = lambda x: int(x)-1
MOD = 998244353 #10**9+7
INF = 1<<60
Yes, No = "Yes", "No"

class MatrixPow:
    def __init__(self, add, zero, mul, one, mat):
        h = len(mat)
        w = len(mat[0])
        assert h == w
        self.n = h
        self.add = add
        self.zero = zero
        self.mul = mul
        self.one = one
        self.mat = self._zeros()
        for i in range(self.n):
            for j in range(self.n):
                self.mat[i][j] = mat[i][j]
    
    def pow(self, k: int):
        mat = self._mat()
        res = self._identity()
        while k != 0:
            z = (k&-k).bit_length()-1
            for _ in range(z): mat = self._mul_mat(mat, mat)
            k >>= z
            k -= 1
            res = self._mul_mat(res, mat)
        return res
    
    def _mat(self):
        res = self._zeros()
        for i in range(self.n):
            for j in range(self.n):
                res[i][j] = self.mat[i][j]
        return res
    
    def _zeros(self):
        return [[self.zero]*self.n for _ in range(self.n)]
    
    def _identity(self):
        ret = self._zeros()
        for i in range(self.n): ret[i][i] = self.one
        return ret
    
    def _mul_mat(self, a, b):
        res = self._zeros()
        for i in range(self.n):
            for j in range(self.n):
                s = self.zero
                for k in range(self.n): s = self.add(s, self.mul(a[i][k], b[k][j]))
                res[i][j] = s
        return res
    
    @staticmethod
    def mul_mat_vec(mat, vec, add, zero, mul):
        n = len(mat)
        res = [zero]*n
        for i in range(n):
            for j in range(n):
                res[i] = add(res[i], mul(mat[i][j], vec[j]))
        return res
# |a, b| |x|   |(a⊗x)⊕(b⊗y)|
# |c, d| |y| = |(c⊗x)⊕(d⊗y)|

def add(a, b): return (a+b)%MOD
zero = 0
def mul(a, b): return (a*b)%MOD
one = 1

def prime(num):
    num = int(num)
    p = []
    if num < 2: return p
    p.append(2)
    memo = [i%2 for i in range(num+1)]
    for i in range(3, num+1, 2):
        if memo[i] == 0: continue
        p.append(i)
        for j in range(i, num+1, i):
            memo[j] = 0
    return p

L = 10**7
P = prime(L)
pset = set(P)
good = []
for p in P:
    if p>>1&1:
        q = p^2
        if q in pset:
            good.append(p)

for _ in range(int(input())):
    N, M = map(int, input().split())
    if N == 1:
        ans = bisect_right(P, M)
    else:
        good_cnt = bisect_right(good, M)
        mat = [[0, 1], [good_cnt*2, 1]]
        MAT = MatrixPow(add, zero, mul, one, mat)
        mat = MAT.pow(N-1)
        vec = [1, good_cnt*2]
        ans = sum(MAT.mul_mat_vec(mat, vec, add, zero, mul))%MOD
    print(ans)

0