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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#411008#6736. Alice and BobLance#AC ✓313ms315904kbC++141.4kb2024-05-14 20:05:502024-05-14 20:05:51

Judging History

你现在查看的是最新测评结果

  • [2024-05-14 20:05:51]
  • 评测
  • 测评结果:AC
  • 用时:313ms
  • 内存:315904kb
  • [2024-05-14 20:05:50]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define ep emplace_back
#define fi first
#define se second
using ll=long long;
using ull=unsigned long long;
#define pi pair<int, int>
#define pll pair<long long,long long>
#ifdef LOCAL
#include"D:/Administrator/Documents/vscode/algo/debug.h"
#else
#define debug(...) 42
#endif
ll mod=998244353;
mt19937 mrand(random_device{}());
//模板区域~~~~~~~
ll qpow(ll a,ll b){
		ll ans=1;
		while(b)
		{
			if(b&1)
			{
				(ans*=a)%=mod;
			}
			b>>=1;
			(a*=a)%=mod;
		}
		return ans;
	};
//模板结束~~~~~~~

signed main(){
#ifndef LOCAL
	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
#endif
#ifdef LOCAL
	freopen("D:/Administrator/Documents/vscode/in.txt","r",stdin);
	freopen("D:/Administrator/Documents/vscode/out.txt","w",stdout);
#endif
	int n;
	cin>>n;
	
	vector<ll> fact(n+1),s(n+1),inv(n+1),ans(n+1);
	fact[0]=1;s[0]=1;
	for(ll i=1;i<=n;i++)
	{
		(fact[i]=fact[i-1]*i%mod)%=mod;
		s[i]=s[i-1]*fact[i]%mod;
	}
	ll tmp=qpow(s[n],mod-2);
	for(int i=n;i>=1;i--){
		inv[i]=tmp*s[i-1]%mod;
		tmp=tmp*fact[i]%mod;
	}
	for(int i=n;i>=1;i--){
		if(i>(n)/2){
			ans[i]=0;
		}else{
			//cout<<i<<endl;
			ans[i]=(ans[i+1]+(fact[n-i]*fact[n-i]%mod)*(inv[n-2*i+1])%mod)%mod;
		}
	}
	// for(int i=1;i<=n;i++){
	// 	cout<<ans[i]<<' ';
	// }cout<<endl;
	if(n&1) ans[1]+=(fact[(n)/2]*fact[(n)/2]%mod);
	cout<<ans[1]%mod;
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3608kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3616kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3520kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3600kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3832kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3472kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3852kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3468kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3520kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3476kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3556kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3672kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3588kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 43ms
memory: 45692kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 236ms
memory: 240068kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 245ms
memory: 257496kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 203ms
memory: 195144kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 108ms
memory: 112960kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 218ms
memory: 220980kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 94ms
memory: 93308kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 311ms
memory: 315608kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 304ms
memory: 315904kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 313ms
memory: 315848kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"