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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#411019 | #8339. Rooted Tree | Errormaker | TL | 1488ms | 6824kb | C++17 | 3.5kb | 2024-05-14 20:12:40 | 2024-05-14 20:12:41 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 9;
template<long long P>
struct ModInt {
public:
ModInt() : v(0) {}
template<typename T>
ModInt(T x) { v = ((long long) x % P + P) % P; }
long long val() const { return v; }
ModInt &operator++() {
++v;
if (v == P)
v = 0;
return *this;
}
ModInt &operator--() {
if (v == 0)
v = P;
--v;
return *this;
}
ModInt operator++(int) {
ModInt oldVal = *this;
++*this;
return oldVal;
}
ModInt operator--(int) {
ModInt oldVal = *this;
--*this;
return oldVal;
}
ModInt &operator+=(const ModInt &rhs) {
v += rhs.v;
v %= P;
return *this;
}
ModInt &operator-=(const ModInt &rhs) {
v -= rhs.v;
v = (v + P) % P;
return *this;
}
ModInt &operator*=(const ModInt &rhs) {
v *= rhs.v;
v %= P;
return *this;
}
ModInt &operator/=(const ModInt &rhs) { return *this = *this * rhs.inv(); }
ModInt operator+() const { return *this; }
ModInt operator-() const { return ModInt() - *this; }
ModInt pow(long long exp) const {
// assert(exp>=0);
ModInt res = 1;
ModInt base = *this;
while (exp) {
if (exp & 1)
res *= base;
base *= base;
exp >>= 1;
}
return res;
}
ModInt inv() const {
// assert(v);
return pow(P - 2);
}
friend ModInt operator+(const ModInt &lhs, const ModInt &rhs) {
ModInt res = lhs;
res += rhs;
return res;
}
friend ModInt operator-(const ModInt &lhs, const ModInt &rhs) {
ModInt res = lhs;
res -= rhs;
return res;
}
friend ModInt operator*(const ModInt &lhs, const ModInt &rhs) {
ModInt res = lhs;
res *= rhs;
return res;
}
friend ModInt operator/(const ModInt &lhs, const ModInt &rhs) {
ModInt res = lhs;
res /= rhs;
return res;
}
friend bool operator==(const ModInt &lhs, const ModInt &rhs) { return lhs.v == rhs.v; }
friend bool operator!=(const ModInt &lhs, const ModInt &rhs) { return lhs.v != rhs.v; }
friend std::istream &operator>>(std::istream &is, ModInt &aim) {
long long tmp;
is >> tmp;
aim = ModInt(tmp);
return is;
}
friend std::ostream &operator<<(std::ostream &os, const ModInt &aim) { return os << aim.val(); }
private:
long long v;
};
using mint = ModInt<MOD>;
mint fact[200005];
mint infact[200005];
void init() {
infact[0] = fact[0] = 1;
for (int i = 1; i <= 200002; i++)
fact[i] = fact[i - 1] * i, infact[i] = infact[i - 1] / i;
}
mint C(int a, int b) {
if (a < b || a < 0 || b < 0) return 0;
return fact[a] * infact[b] * infact[a - b];
}
void Solve() {
int n, k;
cin >> k >> n;
mint avg_dep = 0;
mint yenum = 1;
mint rem = 0;
while (n--) {
mint nxtnum = yenum + k - 1;
rem += avg_dep;
avg_dep = (avg_dep * (yenum - 1) / nxtnum + (k * (avg_dep + 1) / nxtnum));
yenum += k - 1;
}
cout << avg_dep * yenum + rem;
}
int main() {
std::ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
Solve();
}
Details
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Test #1:
score: 100
Accepted
time: 1ms
memory: 6824kb
input:
6 2
output:
18
result:
ok 1 number(s): "18"
Test #2:
score: 0
Accepted
time: 0ms
memory: 6820kb
input:
2 6
output:
600000038
result:
ok 1 number(s): "600000038"
Test #3:
score: 0
Accepted
time: 138ms
memory: 6672kb
input:
83 613210
output:
424200026
result:
ok 1 number(s): "424200026"
Test #4:
score: 0
Accepted
time: 1488ms
memory: 6768kb
input:
48 6713156
output:
198541581
result:
ok 1 number(s): "198541581"
Test #5:
score: 0
Accepted
time: 0ms
memory: 6760kb
input:
1 111
output:
6216
result:
ok 1 number(s): "6216"
Test #6:
score: -100
Time Limit Exceeded
input:
28 7304152