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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#209175#6736. Alice and BobluhanningTL 896ms134980kbC++14903b2023-10-10 11:09:162023-10-10 11:09:16

Judging History

你现在查看的是最新测评结果

  • [2023-10-10 11:09:16]
  • 评测
  • 测评结果:TL
  • 用时:896ms
  • 内存:134980kb
  • [2023-10-10 11:09:16]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e7 + 10;
const int mod = 998244353;
int n, m, k;
string s1, s2;
int h[N], idx, ne[N];
vector<int> pa;
double a, b;
int infact[N];
int fact[N];

int qmi(int a,int k,int p)
{
	int res=1;
	while(k){
		if(k&1) res=res*a%p;
		a=a*a%p;
		k>>=1;
	}
	return res;
}


void solve() {
	cin >> n;
	fact[0]=infact[0]=1;
	for(int i=1;i<=n;i++)
	{
		fact[i]=fact[i-1]*i%mod;
		infact[i]=infact[i-1]*qmi(i,mod-2,mod)%mod;
	}
	int ans = 0;
	for (int i = 1; i <= n+1; i++) {
		
		if (n - i >= i - 1) {
			int t1=fact[n-i]%mod;
			int t2=fact[n-i]*infact[n+1-2*i]%mod;
			ans=(ans+(t1*t2)%mod)%mod;
		}
		
	}
	//cout<<fact[3]<<endl;
	cout << ans << endl;
}


signed main() {
	int t = 1;
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	
	//cin >> t;
	while (t--) {
		solve();
	}
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 7784kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 7764kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 7836kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 7768kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 7760kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 7784kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 7784kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 7728kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 7824kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 7836kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 7708kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 7780kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 1ms
memory: 7716kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 149ms
memory: 30424kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 817ms
memory: 127208kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 896ms
memory: 134980kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 681ms
memory: 103424kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 387ms
memory: 63896kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 756ms
memory: 116340kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 320ms
memory: 54592kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: -100
Time Limit Exceeded

input:

9999998

output:

758172780

result: