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 |
|---|---|---|---|---|---|---|---|---|---|
| #408992 | #6736. Alice and Bob | Phon# | AC ✓ | 592ms | 81860kb | C++23 | 942b | 2024-05-11 14:32:14 | 2024-05-11 14:32:15 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define debug(x) cerr<<#x<<": "<<x<<'\n';
#define int long long
typedef pair<int,int> PII;
const int N = 1e7 + 10, mod = 998244353;
int n, m, k, q, x;
double a, b, s, ops = 1e-4, cnt = 0, t = 0.5;
vector<int> v;
int fac[N];
int Pow (int a, int k) {
int ans = 1ll % mod;
for (; k; k >>= 1, a = a * a % mod)
if (k & 1) ans = ans * a % mod;
return ans;
}
int inv(int x){
return Pow(x,mod - 2);
}
void unit(int m)
{
fac[0] = 1;
for(int i = 1;i <= m;i++)
fac[i] = (fac[i - 1] * i) % mod;
}
void solve(){
cin >> n;
int ans = 0;
for(int i = 1;2 * i - 1 <= n;i++)
ans = (ans + Pow(fac[n - i], 2) * inv(fac[n - 2 * i + 1]) % mod) % mod;
cout << ans;
}
signed main(){
ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
unit(1e7);
// cout.flush();
// int T; cin >> T;
// while(T--)
solve();
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 41ms
memory: 81804kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 40ms
memory: 81668kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 38ms
memory: 81848kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 38ms
memory: 81860kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 41ms
memory: 81792kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 41ms
memory: 81792kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 38ms
memory: 81812kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 45ms
memory: 81788kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 45ms
memory: 81788kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 45ms
memory: 81732kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 38ms
memory: 81860kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 34ms
memory: 81808kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 49ms
memory: 81724kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 116ms
memory: 81848kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 462ms
memory: 81732kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 489ms
memory: 81848kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 368ms
memory: 81792kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 239ms
memory: 81860kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 425ms
memory: 81728kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 197ms
memory: 81784kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 591ms
memory: 81732kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 592ms
memory: 81812kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 587ms
memory: 81708kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"