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洛谷P5245 【模板】多项式快速幂(多项式ln 多项式exp)

2019年03月22日  | 移动技术网IT编程  | 我要评论

陈奕迅 黄伟文,花卉养殖网,订制仓鼠宝宝

题意

题目链接

sol

\(b(x) = \exp(k\ln(a(x)))\)

做完了。。。

复杂度\(o(n\log n)\)

// luogu-judger-enable-o2
// luogu-judger-enable-o2
#include<bits/stdc++.h> 
#define pair pair<int, int>
#define mp(x, y) make_pair(x, y)
#define fi first
#define se second
#define ll long long 
#define ull unsigned long long 
#define fin(x) {freopen(#x".in","r",stdin);}
#define fout(x) {freopen(#x".out","w",stdout);}
using namespace std;
const int maxn = 4e5 + 10, inf = 1e9 + 10, inv2 = 499122177;
const double eps = 1e-9, pi = acos(-1);
const int g = 3, mod = 998244353;
inline int read() {
    char c = getchar(); int x = 0, f = 1;
    while(c < '0' || c > '9') {if(c == '-') f = -1; c = getchar();}
    while(c >= '0' && c <= '9') x = (1ll * x * 10 + c - '0') % mod, c = getchar();
    return x * f;
}
int n, k, a[maxn], b[maxn];
namespace poly {
    int rev[maxn], gpow[maxn], a[maxn], b[maxn], c[maxn], lim;
    
    template <typename a, typename b> inline ll add(a x, b y) {if(x + y < 0) return x + y + mod; return x + y >= mod ? x + y - mod : x + y;}
    template <typename a, typename b> inline void add2(a &x, b y) {if(x + y < 0) x = x + y + mod; else x = (x + y >= mod ? x + y - mod : x + y);}
    template <typename a, typename b> inline ll mul(a x, b y) {return 1ll * x * y % mod;}
    template <typename a, typename b> inline void mul2(a &x, b y) {x = (1ll * x * y % mod + mod) % mod;}
    int fp(int a, int p, int p = mod) {
        int base = 1;
        for(; p; p >>= 1, a = 1ll * a * a % p) if(p & 1) base = 1ll * base *  a % p;
        return base;
    }
    int getlen(int x) {
        int lim = 1;
        while(lim <= x) lim <<= 1;
        return lim;
    }
    int getlen2(int x) {
        int lim = 1; 
        while(lim <= x) lim <<= 1;
        return lim;
    }
    int getorigin(int x) {//¼æëãô­¸ù 
        static int q[maxn]; int tot = 0, tp = x - 1;
        for(int i = 2; i * i <= tp; i++) if(!(tp % i)) {q[++tot] = i;while(!(tp % i)) tp /= i;}
        if(tp > 1) q[++tot] = tp;
        for(int i = 2, j; i <= x - 1; i++) {
            for(j = 1; j <= tot; j++) if(fp(i, (x - 1) / q[j], x) == 1) break;
            if(j == tot + 1) return i;
        }
    }
    void init(int lim) {
        for(int i = 1; i <= lim; i++) gpow[i] = fp(g, (mod - 1) / i);
    }
    void ntt(int *a, int lim, int opt) {
        int len = 0; for(int n = 1; n < lim; n <<= 1) ++len; 
        for(int i = 1; i <= lim; i++) rev[i] = (rev[i >> 1] >> 1) | ((i & 1) << (len - 1));
        for(int i = 0; i <= lim; i++) if(i < rev[i]) swap(a[i], a[rev[i]]);
        for(int mid = 1; mid < lim; mid <<= 1) {
            int wn = gpow[mid << 1];
            for(int i = 0; i < lim; i += (mid << 1)) {
                for(int j = 0, w = 1; j < mid; j++, w = mul(w, wn)) {
                    int x = a[i + j], y = mul(w, a[i + j + mid]);
                    a[i + j] = add(x, y), a[i + j + mid] = add(x, -y);
                }
            }
        }
        if(opt == -1) {
            reverse(a + 1, a + lim);
            int inv = fp(lim, mod - 2);
            for(int i = 0; i <= lim; i++) mul2(a[i], inv);
        }
    }
    void mul(int *a, int *b, int n, int m) {
        memset(a, 0, sizeof(a)); memset(b, 0, sizeof(b));
        int lim = 1, len = 0; 
        while(lim <= n + m) len++, lim <<= 1;
        for(int i = 0; i <= n; i++) a[i] = a[i]; 
        for(int i = 0; i <= m; i++) b[i] = b[i];
        ntt(a, lim, 1); ntt(b, lim, 1);
        for(int i = 0; i <= lim; i++) b[i] = mul(b[i], a[i]);
        ntt(b, lim, -1);
        for(int i = 0; i <= n + m; i++) b[i] = b[i];
        memset(a, 0, sizeof(a)); memset(b, 0, sizeof(b));
    }
    void inv(int *a, int *b, int len) {//b1 = 2b - a1 * b^2 
        if(len == 1) {b[0] = fp(a[0], mod - 2); return ;}
        inv(a, b, len >> 1);
        for(int i = 0; i < len; i++) a[i] = a[i], b[i] = b[i];
        ntt(a, len << 1, 1); ntt(b, len << 1, 1);
        for(int i = 0; i < (len << 1); i++) mul2(a[i], mul(b[i], b[i]));
        ntt(a, len << 1, -1);
        for(int i = 0; i < len; i++) add2(b[i], add(b[i], -a[i]));
        for(int i = 0; i < (len << 1); i++) a[i] = b[i] = 0;
    }
    void dao(int *a, int *b, int len) {
        for(int i = 1; i < len; i++) b[i - 1] = mul(i, a[i]); b[len - 1] = 0;
    }
    void ji(int *a, int *b, int len) {
        for(int i = 1; i < len; i++) b[i] = mul(a[i - 1], fp(i, mod - 2)); b[0] = 0;
    }
    void ln(int *a, int *b, int len) {//g(a) = \frac{a}{a'} qiudao zhihou jifen 
        static int a[maxn], b[maxn];
        dao(a, a, len); 
        inv(a, b, len);
        ntt(a, len << 1, 1); ntt(b, len << 1, 1);
        for(int i = 0; i < (len << 1); i++) b[i] = mul(a[i], b[i]);
        ntt(b, len << 1, -1); 
        ji(b, b, len << 1);
        memset(a, 0, sizeof(a)); memset(b, 0, sizeof(b));
    }
    void exp(int *a, int *b, int len) {//f(x) = f_0 (1 - lnf_0 + a) but code ..why....
        if(len == 1) return (void) (b[0] = 1);
        exp(a, b, len >> 1); ln(b, c, len);
        c[0] = add(a[0] + 1, -c[0]);
        for(int i = 1; i < len; i++) c[i] = add(a[i], -c[i]);
        ntt(c, len << 1, 1); ntt(b, len << 1, 1);
        for(int i = 0; i < (len << 1); i++) mul2(b[i], c[i]);
        ntt(b, len << 1, -1);
        for(int i = len; i < (len << 1); i++) c[i] = b[i] = 0;
    }
    void sqrt(int *a, int *b, int len) {
        static int b[maxn];
        ln(a, b, len);
        for(int i = 0; i < len; i++) b[i] = mul(b[i], inv2);
        exp(b, b, len); 
    }
    void div(int *f, int *g, int *q, int *r, int n, int m) {//f(n) = g(m) * q(n - m + 1) + r(m) 
        static int ginv[maxn]; memset(ginv, 0, sizeof(ginv));
        reverse(f, f + n + 1); reverse(g, g + m + 1);
        inv(g, ginv, getlen2(n - m));//why not m
        mul(f, ginv, n - m, n - m);
        for(int i = 0; i <= n - m; i++) q[i] = ginv[i];
        reverse(q, q + n - m + 1);
        reverse(f, f + n + 1); reverse(g, g + m + 1);
        mul(q, g, n - m, m);
        for(int i = 0; i < m; i++) r[i] = add(f[i], -g[i]);
    }
    void pow(int *a, int *b, int p, int n, int len) {
        static int tx[maxn], ty[maxn]; memset(tx, 0, sizeof(tx)); memset(ty, 0, sizeof(ty));
        ln(a, tx, len);
        for(int i = 0; i < n; i++) ty[i] = mul(p, tx[i]);
        exp(ty, b, len);
    }
};
using namespace poly; 
signed main() {
    n = read(); k = read();
    init(4 * n);
    for(int i = 0; i < n; i++) a[i] = read();
    pow(a, b, k, n, getlen(n));
    for(int i = 0; i < n; i++) cout << b[i] << ' ';
    return 0;
}
/*
4 1242412412412412412421421
1 1 0 0

*/

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