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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#408747 | #8339. Rooted Tree | Nelofus | AC ✓ | 289ms | 198900kb | C++20 | 2.2kb | 2024-05-10 23:01:09 | 2024-05-10 23:01:09 |
Judging History
answer
// Code by Heratino & Nelofus
// Narcissus & ?????????
#include <bits/stdc++.h>
using i64 = long long;
//{{{??????? ? ?????
template<typename Ta, typename Tb>
inline void chkmax(Ta &a, const Tb &b) {if (a < b) a = b;}
template<typename Ta, typename Tb>
inline void chkmin(Ta &a, const Tb &b) {if (a > b) a = b;}
char buf[1 << 20], *P1, *P2;
inline char gc() {
if (P1 == P2)
P2 = (P1 = buf) + fread(buf, 1, 1 << 20, stdin);
return P1 == P2 ? EOF : *P1++;
}
template<typename T>
inline void read(T &ans) {
ans = 0;
T w = 1;
char c = gc();
while (!isdigit(c)) {
if (c == '-') w = -1;
c = gc();
}
while (isdigit(c)) {
ans = (ans << 3) + (ans << 1) + (c ^ 48);
c = gc();
}
ans *= w;
}
template<typename T, typename ...Ts>
void read(T &a, Ts&... other) {
read(a);
read(other...);
}
//}}}
constexpr int mod = 1e9 + 9;
constexpr int N = 1e7 + 10;
inline int Plus(const int &x, const int &y) {return x + y >= mod ? x + y - mod : x + y;}
inline int Minu(const int &x, const int &y) {return x - y < 0 ? x - y + mod : x - y;}
inline int f_pow(int x, int k) {
int base = 1;
for (; k; k >>= 1, x = 1ll * x * x % mod)
if (k & 1)
base = 1ll * base * x % mod;
return base;
}
int m, k;
int ifac[N];
int fac[N];
int ED[N];
int pinvf[N], pinvq[N];
inline int inv(int x) {
return x ? 1ll * ifac[x] * fac[x - 1] % mod : 1;
}
int main() {
#ifdef HeratinoNelofus
freopen("input.txt", "r", stdin);
#endif
fac[0] = 1;
for (int i = 1; i < N; i++)
fac[i] = 1ll * fac[i - 1] * i % mod;
ifac[N - 1] = f_pow(fac[N - 1], mod - 2);
for (int i = N - 2; i >= 0; i--)
ifac[i] = 1ll * ifac[i + 1] * (i + 1) % mod;
read(m, k);
auto invpinv = [&](const int &x) -> int {
return Plus(1ll * (x - 1) * (m - 1) % mod, 1);
};
pinvf[0] = 1;
for (int i = 1; i <= k; i++)
pinvf[i] = 1ll * pinvf[i - 1] * invpinv(i) % mod;
pinvq[k] = f_pow(pinvf[k], mod - 2);
for (int i = k - 1; i >= 0; i--)
pinvq[i] = 1ll * pinvq[i + 1] * invpinv(i + 1) % mod;
ED[0] = 0;
int ans = 0;
for (int i = 1; i <= k; i++) {
int pinv = 1ll * pinvq[i] * pinvf[i - 1] % mod;
ans = Plus(ans, Plus(1ll * ED[i - 1] * pinv % mod, 1));
ED[i] = 1ll * ED[i - 1] * (Plus(1ll * i * (m - 1) % mod, 1)) % mod * pinv % mod;
ED[i] = Plus(ED[i], m);
}
std::cout << 1ll * m * ans % mod << '\n';
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 96ms
memory: 81712kb
input:
6 2
output:
18
result:
ok 1 number(s): "18"
Test #2:
score: 0
Accepted
time: 95ms
memory: 81724kb
input:
2 6
output:
600000038
result:
ok 1 number(s): "600000038"
Test #3:
score: 0
Accepted
time: 101ms
memory: 88968kb
input:
83 613210
output:
424200026
result:
ok 1 number(s): "424200026"
Test #4:
score: 0
Accepted
time: 205ms
memory: 160380kb
input:
48 6713156
output:
198541581
result:
ok 1 number(s): "198541581"
Test #5:
score: 0
Accepted
time: 76ms
memory: 81788kb
input:
1 111
output:
6216
result:
ok 1 number(s): "6216"
Test #6:
score: 0
Accepted
time: 235ms
memory: 167308kb
input:
28 7304152
output:
457266679
result:
ok 1 number(s): "457266679"
Test #7:
score: 0
Accepted
time: 166ms
memory: 129644kb
input:
38 4101162
output:
232117382
result:
ok 1 number(s): "232117382"
Test #8:
score: 0
Accepted
time: 268ms
memory: 198048kb
input:
51 9921154
output:
340670552
result:
ok 1 number(s): "340670552"
Test #9:
score: 0
Accepted
time: 120ms
memory: 102728kb
input:
79 1801157
output:
620550406
result:
ok 1 number(s): "620550406"
Test #10:
score: 0
Accepted
time: 196ms
memory: 145200kb
input:
22 5417157
output:
457449071
result:
ok 1 number(s): "457449071"
Test #11:
score: 0
Accepted
time: 157ms
memory: 119244kb
input:
25 3210162
output:
36368303
result:
ok 1 number(s): "36368303"
Test #12:
score: 0
Accepted
time: 162ms
memory: 115996kb
input:
67 2919160
output:
935195555
result:
ok 1 number(s): "935195555"
Test #13:
score: 0
Accepted
time: 265ms
memory: 182612kb
input:
77 8613163
output:
482832472
result:
ok 1 number(s): "482832472"
Test #14:
score: 0
Accepted
time: 280ms
memory: 198792kb
input:
90 10000000
output:
275581651
result:
ok 1 number(s): "275581651"
Test #15:
score: 0
Accepted
time: 289ms
memory: 198900kb
input:
99 9999999
output:
126087169
result:
ok 1 number(s): "126087169"
Test #16:
score: 0
Accepted
time: 285ms
memory: 198896kb
input:
100 10000000
output:
451590067
result:
ok 1 number(s): "451590067"
Extra Test:
score: 0
Extra Test Passed