QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #403522 | #6736. Alice and Bob | CCF_NOI# | AC ✓ | 104ms | 81824kb | C++14 | 665b | 2024-05-02 14:20:36 | 2024-05-02 14:20:37 |
Judging History
answer
#include<iostream>
#include<cmath>
using namespace std;
#define For(i,l,r) for(int i=l;i<=r;i++)
#define FOR(i,r,l) for(int i=r;i>=l;i--)
#define ll long long
#define P 998244353
#define N 10000005
int n,fc[N],inv[N];
ll get()
{
ll x;
scanf("%lld",&x);
return x;
}
int pow(int a,int b)
{
int ans=1;
while(b)
{
if(b&1)ans=1ll*ans*a%P;
a=1ll*a*a%P;
b>>=1;
}
return ans;
}
int main()
{
int n=get();
fc[0]=1;
For(i,1,n)fc[i]=1ll*fc[i-1]*i%P;
inv[n]=pow(fc[n],P-2);
FOR(i,n-1,0)inv[i]=1ll*inv[i+1]*(i+1)%P;
int ans=0;
For(i,1,(n+1)/2)ans=(ans+1ll*fc[n-i]*fc[n-i]%P*inv[n-i*2+1])%P;
cout<<ans<<'\n';
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 3568kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3668kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3564kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3716kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3712kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3512kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3716kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3772kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3696kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3520kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3664kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 3520kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 3528kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 13ms
memory: 14276kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 77ms
memory: 62728kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 93ms
memory: 67300kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 68ms
memory: 51676kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 29ms
memory: 31176kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 90ms
memory: 57960kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 34ms
memory: 26332kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 98ms
memory: 81640kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 83ms
memory: 81824kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 104ms
memory: 81756kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"