QOJ.ac
QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#413443 | #6736. Alice and Bob | HHY_zZhu# | AC ✓ | 104ms | 159336kb | C++14 | 1.9kb | 2024-05-17 16:01:10 | 2024-05-17 16:01:12 |
Judging History
answer
template<class T,class T2> int chkmn(T &a,T2 b){return a>b?a=b,1:0;}
template<class T,class T2> int chkmx(T &a,T2 b){return a<b?a=b,1:0;}
#include <bits/stdc++.h>
using namespace std;
#define V vector
#define all0(x) (x).begin(),(x).end()
#define all1(x) (x).begin()+1,(x).end()
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define cin std::cin
#define cout std::cout
typedef long long LL;
typedef pair<int, int> pi;
typedef pair<LL, LL> pl;
#ifdef LOCAL
#include "C:/Users/lijia/Desktop/vscode/algo/debug.h"
#else
#define debug(...) 42
#endif
//const int MN = 2e5 + 20;//MaxN 记得改一下
const int INF = 2e9+1000;//INF
const LL INFLL = 8e18+1000;//INF long long
mt19937 mrand(random_device{}());
//模板区域~~~~~~~
//模板结束~~~~~~~
const int mod = 998244353;
LL qpow(int x, LL k) {
LL ans = 1;
while(k) {
if(k & 1) ans = ans * x % mod;
x = 1LL * x * x % mod;
k /= 2;
}
return ans;
}
LL inv(int x) {
return qpow(x, mod - 2);
}
void solve() {
int n; cin >> n;
V<LL> fac(n + 1);
V<LL> ifac(n + 1);
fac[0] = 1;
for(int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i % mod;
ifac[n] = inv(fac[n]);
for(int i = n - 1; i >= 0; i--) {
ifac[i] = ifac[i + 1] * (i + 1) % mod;
}
auto A = [&](int x, int k) -> LL {
if(k > x || k < 0) return 0;
return fac[x] * ifac[x - k] % mod;
};
LL ans = 0;
for(int i = 1; i <= n; i++) {
//A(n - i, i - 1) * fac(n - i);
ans += A(n - i, i - 1) * fac[n - i] % mod;
if(ans >= mod) ans -= mod;
}
cout << ans << endl;
}
int32_t main() {
#ifndef LOCAL
ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
#endif
int tt=1;
//cin >> tt;
while (tt--)
solve();
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3488kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3756kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3820kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3552kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3616kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3556kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3816kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3548kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3616kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3784kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3596kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 3624kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 0ms
memory: 3548kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 15ms
memory: 24340kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 76ms
memory: 121516kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 81ms
memory: 130464kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 69ms
memory: 99004kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 35ms
memory: 58164kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 76ms
memory: 112028kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 35ms
memory: 48128kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 104ms
memory: 159336kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 104ms
memory: 159296kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 104ms
memory: 159244kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"