QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#133766 | #6736. Alice and Bob | bigJ | AC ✓ | 121ms | 81764kb | C++20 | 1.8kb | 2023-08-02 13:56:40 | 2023-08-02 13:56:44 |
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 = 1e7;
constexpr int P = 998244353;
bool is_init;
int fac[N + 1], invfac[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;
}
invfac[N] = power(fac[N], P - 2);
for (int i = N; i >= 1; i--) {
invfac[i - 1] = 1LL * invfac[i] * i % P;
}
is_init = true;
}
int binom(int n, int m) {
if (!is_init) init();
if (n < m || m < 0) {
return 0;
}
return 1LL * fac[n] * invfac[m] % P * invfac[n - m] % P;
}
int main() {
std::cin.tie(nullptr);
std::ios::sync_with_stdio(false);
init();
int n;
std::cin >> n;
int ans = fac[n - 1];
for (int i = 2; i <= n; i++) {
ans = (1LL * ans + 1LL * fac[n - i] % P * binom(n - i, i - 1) % P * fac[i - 1] % P) % P;
}
std::cout << ans << "\n";
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 72ms
memory: 81760kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 89ms
memory: 81652kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 80ms
memory: 81500kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 80ms
memory: 81536kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 83ms
memory: 81656kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 84ms
memory: 81600kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 80ms
memory: 81764kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 81ms
memory: 81656kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 77ms
memory: 81600kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 72ms
memory: 81536kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 81ms
memory: 81508kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 84ms
memory: 81544kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 81ms
memory: 81548kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 90ms
memory: 81760kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 112ms
memory: 81700kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 109ms
memory: 81596kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 110ms
memory: 81588kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 101ms
memory: 81704kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 116ms
memory: 81588kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 96ms
memory: 81612kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 121ms
memory: 81544kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 121ms
memory: 81588kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 120ms
memory: 81760kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"