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| #include <cstdio>
#include <algorithm>
using namespace std;
template <class Type>
void read (Type &x)
{
char c;
bool flag = false;
while ((c = getchar()) < '0' || c > '9')
flag |= c == '-';
x = c - '0';
while ((c = getchar()) >= '0' && c <= '9')
x = (x << 3) + (x << 1) + c - '0';
if (flag) x = ~x + 1;
}
template <class Type, class ...Rest>
void read (Type &x, Rest &...y) { read(x); read(y...); }
template <class Type>
void write (Type x)
{
if (x < 0) putchar('-'), x = ~x + 1;
if (x > 9) write(x / 10);
putchar('0' + x % 10);
}
typedef __int128 L;
typedef long long LL;
const int N = 5e5 + 10, p = 1e9 + 7, p1 = 998244353, p2 = 1004535809, p3 = 469762049;
const L inf = (L)N * p * p, mul = (L)p1 * p2 * p3;
int binpow (int b, int k = p - 2)
{
int res = 1;
for (; k; k >>= 1, b = (LL)b * b % p)
if (k & 1) res = (LL)res * b % p;
return res;
}
int fact[N], ifact[N];
template <const int &mod>
struct NTT
{
int rev[N];
int binpow (int b, int k = mod - 2)
{
int res = 1;
for (; k; k >>= 1, b = (LL)b * b % mod)
if (k & 1) res = (LL)res * b % mod;
return res;
}
void ntt (int *x, int bit, int op)
{
int tot = 1 << bit;
for (int i = 0; i < tot; ++i)
if ((rev[i] = rev[i >> 1] >> 1 | ((i & 1) << bit - 1)) > i)
swap(x[rev[i]], x[i]);
for (int mid = 1; mid < tot; mid <<= 1)
{
int w1 = binpow(3, (mod - 1) / (mid << 1));
if (!~op) w1 = binpow(w1);
for (int i = 0; i < tot; i += mid << 1)
for (int j = 0, k = 1; j < mid; ++j, k = (LL)k * w1 % mod)
{
int p = x[i | j], q = (LL)k * x[i | j | mid] % mod;
x[i | j] = (p + q) % mod, x[i | j | mid] = (p - q) % mod;
}
}
if (~op) return;
int itot = binpow(tot);
for (int i = 0; i < tot; ++i)
x[i] = (LL)x[i] * itot % mod;
}
void PolyMul (int n, int *f, int m, int *g, int nm, int *w)
{
static int A[N], B[N];
for (int i = 0; i < n; ++i) A[i] = f[i] % mod;
for (int i = 0; i < m; ++i) B[i] = g[i] % mod;
int bit = 1;
while (n + m - 1 > 1 << bit) ++bit;
int tot = 1 << bit;
for (int i = n; i < tot; ++i) A[i] = 0;
for (int i = m; i < tot; ++i) B[i] = 0;
ntt(A, bit, 1), ntt(B, bit, 1);
for (int i = 0; i < tot; ++i)
w[i] = (LL)A[i] * B[i] % mod;
ntt(w, bit, -1);
for (int i = 0; i < nm; ++i) w[i] = (w[i] + mod) % mod;
for (int i = nm; i < tot; ++i) w[i] = 0;
}
};
NTT <p1> q1; NTT <p2> q2; NTT <p3> q3;
const L k1 = (L)p2 * p3 * q1.binpow((LL)p2 * p3 % p1), k2 = (L)p1 * p3 * q2.binpow((LL)p1 * p3 % p2), k3 = (L)p1 * p2 * q3.binpow((LL)p1 * p2 % p3);
int CRT (int x1, int x2, int x3)
{
L res = (x1 * k1 + x2 * k2 + x3 * k3) % mul;
if (res >= inf) res -= mul;
if (res <= -inf) res += mul;
return res % p;
}
void PolyMul (int n, int *f, int m, int *g, int nm, int *w)
{
static int A[N], B[N], C[N];
q1.PolyMul(n, f, m, g, nm, A);
q2.PolyMul(n, f, m, g, nm, B);
q3.PolyMul(n, f, m, g, nm, C);
for (int i = 0; i < nm; ++i)
w[i] = CRT(A[i], B[i], C[i]);
}
void PolyCalc (int n, LL m, int *g)
{
if (m == 1)
{
for (int i = 1; i < n; ++i) g[i] = 1;
return;
}
PolyCalc(n, m >> 1, g);
static int A[N], B[N];
A[0] = B[0] = 0;
for (int i = 1, s = binpow(2, (m >> 1) % (p - 1)), t = s; i < n; ++i, t = (LL)t * s % p)
{
A[i] = (LL)g[i] * t % p * ifact[i] % p;
B[i] = (LL)g[i] * ifact[i] % p;
}
PolyMul(n, A, n, B, n, A);
for (int i = 1; i < n; ++i)
g[i] = (LL)A[i] * fact[i] % p;
if (!(m & 1)) return;
A[0] = B[0] = 0;
for (int i = 1; i < n; ++i)
{
A[i] = (LL)g[i] * binpow(2, i) % p * ifact[i] % p;
B[i] = ifact[i];
}
PolyMul(n, A, n, B, n, A);
for (int i = 1; i < n; ++i)
g[i] = (LL)A[i] * fact[i] % p;
}
void init ()
{
fact[0] = 1;
for (int i = 1; i < N; ++i)
fact[i] = (LL)fact[i - 1] * i % p;
ifact[N - 1] = binpow(fact[N - 1]);
for (int i = N - 1; i; --i)
ifact[i - 1] = (LL)ifact[i] * i % p;
}
int main ()
{
init();
LL n; int m;
static int A[N];
read(n, m);
PolyCalc(m + 1, n, A);
int res = 0;
for (int i = 1; i <= m; ++i)
res = (res + (LL)A[i] * ifact[i] % p * ifact[m - i]) % p;
write(((LL)res * fact[m] % p + p) % p);
return 0;
}
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