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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#133803 | #6736. Alice and Bob | bigJ | RE | 11ms | 11416kb | C++20 | 2.0kb | 2023-08-02 14:13:17 | 2023-08-02 14:13:18 |
Judging History
answer
#include <bits/stdc++.h>
template<typename T, std::size_t N> std::istream& operator>>(std::istream& is, std::array<T, N>& v) { for (auto& i : v) is >> i; return is; }
template<typename T, std::size_t N> std::ostream& operator<<(std::ostream& os, std::array<T, N>& v) { for (auto& i : v) os << i << " "; return os; }
template<typename T> std::istream& operator>>(std::istream& is, std::vector<T>& v) { for (auto& i : v) is >> i; return is; }
template<typename T> std::ostream& operator<<(std::ostream& os, std::vector<T>& v) { for (auto& i : v) os << i << " "; return os; }
template<typename T> auto dbug(const std::initializer_list<T>& a) { std::cerr << "dbug: "; for (auto& i : a) std::cerr << i << " "; std::cerr << std::endl; }
using i64 = long long;
constexpr int N = 1e6;
constexpr int P = 998244353;
bool is_init;
int _fac[N + 1], _ifac[N + 1];
constexpr i64 power(i64 a, i64 b) {
i64 res = 1;
for (; b; b /= 2, a = a * a % P) {
if (b % 2) {
res = res * a % P;
}
}
return res;
}
void init() {
_fac[0] = 1;
for (int i = 1; i <= N; i++) {
_fac[i] = 1LL * _fac[i - 1] * i % P;
}
_ifac[N] = power(_fac[N], P - 2);
for (int i = N; i >= 1; i--) {
_ifac[i - 1] = 1LL * _ifac[i] * i % P;
}
is_init = true;
}
int fac(int n) {
if (!is_init) init();
return n < 0 ? 0 : _fac[n];
}
int ifac(int n) {
if (!is_init) init();
return n < 0 ? 0 : _ifac[n];
}
int binom(int n, int m) {
if (!is_init) init();
if (n < m || m < 0) {
return 0;
}
return 1LL * _fac[n] * _ifac[m] % P * _ifac[n - m] % P;
}
int main() {
std::cin.tie(nullptr);
std::ios::sync_with_stdio(false);
int n;
std::cin >> n;
int ans = fac(n - 1);
for (int i = 2; i <= n; i++) {
ans = (ans + (1LL * fac(n - i) * fac(n - i) % P * ifac(n - i - (i - 1)) % P)) % P;
}
std::cout << ans << "\n";
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 5ms
memory: 11180kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 11ms
memory: 11228kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 7ms
memory: 11276kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 10ms
memory: 11408kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 11ms
memory: 11348kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 7ms
memory: 11228kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 11ms
memory: 11344kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 11ms
memory: 11268kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 7ms
memory: 11388kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 7ms
memory: 11300kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 11ms
memory: 11280kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 11ms
memory: 11296kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 7ms
memory: 11416kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: -100
Runtime Error
input:
1361956