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 |
|---|---|---|---|---|---|---|---|---|---|
| #404894 | #6736. Alice and Bob | qzuser | AC ✓ | 618ms | 83732kb | C++17 | 871b | 2024-05-04 21:36:00 | 2024-05-04 21:36:01 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
const int mod = 998244353;
const int N = 1e7 + 10;
int f[N],inv[N];
int qmi(int a, int b)
{
int res = 1;
while (b)
{
if (b & 1) res = res * a % mod;
a = a * a % mod;
b >>= 1;
}
return res;
}
signed main()
{
f[0]=1;
f[1]=1;
inv[0]=1;
inv[1]=1;
for(int i=2;i<=N-1;i++){
f[i]=f[i-1]*i%mod;
//inv[i]=inv[i-1]*qmi(i,mod-2)%mod;
}
int n;cin>>n;
int ans=0;
for(int i=1;i<=n;i++){
if(n-2*i+2>0){
int bd = 1;
bd = bd * f[n - i] % mod * qmi(f[n - 2 * i + 1], mod - 2) % mod;
// for(int j=n-2*i+2;j<=n-i;j++){
// bd=bd*j%mod;
// }
ans=ans+f[n-i]*bd%mod;
}
}
cout<<ans%mod;
}
详细
Test #1:
score: 100
Accepted
time: 49ms
memory: 83540kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 40ms
memory: 82800kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 52ms
memory: 83580kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 53ms
memory: 83052kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 8ms
memory: 83024kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 53ms
memory: 83212kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 47ms
memory: 81824kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 52ms
memory: 83572kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 48ms
memory: 81708kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 53ms
memory: 82548kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 12ms
memory: 81956kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 52ms
memory: 82204kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 52ms
memory: 81768kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 129ms
memory: 81768kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 470ms
memory: 82728kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 486ms
memory: 82260kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 396ms
memory: 83720kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 251ms
memory: 83732kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 440ms
memory: 81912kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 171ms
memory: 83060kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 618ms
memory: 81928kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 611ms
memory: 82440kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 611ms
memory: 83720kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"