大数质因数分解模板

合集 - 模板(41)

1.并查集模板2023-10-312.求质因数模板2023-10-313.二分图最大匹配模板(匈牙利算法)2023-12-024.欧拉函数模板2023-11-305.ST表模板2023-11-266.快速幂模板2023-10-317.字典树模板2023-12-048.矩阵模板2023-12-059.Dijkstra单源最短路模板2023-12-0910.最近公共祖先模板(LCA)2023-12-1211.拓扑排序模板2023-12-1212.区间素数筛模板2023-12-1613.Kruskal和Prim模板2023-12-2414.树状数组模板2023-12-2615.二维坐标离散化模板2024-03-0716.单点修改区间查最值-树状数组模板2024-03-1117.KMP模板2024-03-1118.二叉搜索树模板2024-03-3019.DIjkstra进阶模板 路径记录 按权重(结点数最小等)记录2024-03-3120.判断负环模板2024-04-2821.Exgcd 模板2024-05-0322.压位高精度模板2024-05-0623.线段树模板2024-05-1224.扫描线模板2024-05-1825.莫队模板2024-07-1726.带修莫队模板2024-07-1727.SCC缩点模板2024-07-1828.取模+组合数2024-07-2429.FFT 高精度乘法模板2024-07-2430.字符串自然溢出哈希/单哈希/双哈希模板2024-07-2531.树模板2024-07-2732.dsu on tree 模板2024-07-2833.线段树模板重制2024-08-0334.主席树模板2024-08-07

35.大数质因数分解模板2024-08-08

36.线段树合并模板2024-08-0937.int128输入输出流2024-08-0938.Meissel_Lehmer模板2024-08-0939.浮点高精度2024-08-1340.自适应辛普森法2024-10-0241.unordered_map随机底数种子2024-10-07

收起

jiangly的（偷一下

i64 mul(i64 a, i64 b, i64 m) {
    return static_cast<__int128>(a) * b % m;
}
i64 power(i64 a, i64 b, i64 m) {
    i64 res = 1 % m;
    for (; b; b >>= 1, a = mul(a, a, m))
        if (b & 1)
            res = mul(res, a, m);
    return res;
}
bool isprime(i64 n) {
    if (n < 2)
        return false;
    static constexpr int A[] = {2, 3, 5, 7, 11, 13, 17, 19, 23};
    int s = __builtin_ctzll(n - 1);
    i64 d = (n - 1) >> s;
    for (auto a : A) {
        if (a == n)
            return true;
        i64 x = power(a, d, n);
        if (x == 1 || x == n - 1)
            continue;
        bool ok = false;
        for (int i = 0; i < s - 1; ++i) {
            x = mul(x, x, n);
            if (x == n - 1) {
                ok = true;
                break;
            }
        }
        if (!ok)
            return false;
    }
    return true;
}
std::vector<i64> factorize(i64 n) {
    std::vector<i64> p;
    std::function<void(i64)> f = [&](i64 n) {
        if (n <= 10000) {
            for (int i = 2; i * i <= n; ++i)
                for (; n % i == 0; n /= i)
                    p.push_back(i);
            if (n > 1)
                p.push_back(n);
            return;
        }
        if (isprime(n)) {
            p.push_back(n);
            return;
        }
        auto g = [&](i64 x) {
            return (mul(x, x, n) + 1) % n;
        };
        i64 x0 = 2;
        while (true) {
            i64 x = x0;
            i64 y = x0;
            i64 d = 1;
            i64 power = 1, lam = 0;
            i64 v = 1;
            while (d == 1) {
                y = g(y);
                ++lam;
                v = mul(v, std::abs(x - y), n);
                if (lam % 127 == 0) {
                    d = std::gcd(v, n);
                    v = 1;
                }
                if (power == lam) {
                    x = y;
                    power *= 2;
                    lam = 0;
                    d = std::gcd(v, n);
                    v = 1;
                }
            }
            if (d != n) {
                f(d);
                f(n / d);
                return;
            }
            ++x0;
        }
    };
    f(n);
    std::sort(p.begin(), p.end());
    return p;
}