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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#407972#6736. Alice and Bobzhoujiu#AC ✓140ms159908kbC++141.3kb2024-05-09 15:29:552024-05-09 15:29:57

Judging History

你现在查看的是最新测评结果

  • [2024-05-09 15:29:57]
  • 评测
  • 测评结果:AC
  • 用时:140ms
  • 内存:159908kb
  • [2024-05-09 15:29:55]
  • 提交

answer

#include<bits/stdc++.h>
#define int long long
using namespace std;

const int mod=998244353,N=1e7+10;

int n,m;
int fact[N],infact[N];

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

int C(int a,int b)
{
    if(b>a) return 0;
    return fact[a]*infact[b]%mod*infact[a-b]%mod;
}

void solve()
{
    cin>>n;
	// vector<int>a(n);
	// for(int i=0;i<n;i++){
	// 	a[i] = i+1;
	// }
	// vector<int>t = a;
	// int c = 0;
	// do{
	// 	int mn = a[0];
	// 	for(int i=0;i<a[0];i++){
	// 		mn = min(mn,a[i]);
	// 	}
	// 	if(mn==a[0]){
	// 		c++;
	// 	}
	// 	 next_permutation(a.begin(),a.end());
	// }while(a != t);
	// cout<<c<<'\n';

	fact[0]=infact[0]=1;
	for(int i=1;i<=n;i++)
	{
		fact[i]=fact[i-1]*i%mod;
		// cout<<fact[i]<<' '<<infact[i]<<'\n';
	}
	infact[n] = qmi(fact[n], mod - 2);
	for(int i = n -1; i >= 1; i--)
	{
		infact[i] = infact[i + 1] * (i + 1) % mod;
	}

	// cout<<C(4,2)<<'\n';

	int res=0;
	for(int i=1;i<=n;i++)
	{
		res=(res+C(n-i,i-1)*fact[i-1]%mod*fact[n-i]%mod)%mod;
	}

	// res=((fact[n]-res)%mod+mod)%mod;
	cout<<res<<'\n';
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    int t=1;
    // cin>>t;

    while(t--)
        solve();

    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 5572kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 3628kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3584kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 3588kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3572kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3624kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 1ms
memory: 3584kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3632kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3664kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3660kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 1ms
memory: 3624kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3676kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3632kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 15ms
memory: 24864kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 104ms
memory: 122016kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 111ms
memory: 130856kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 76ms
memory: 101432kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 48ms
memory: 59472kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 99ms
memory: 113456kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 39ms
memory: 49648kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 128ms
memory: 159908kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 140ms
memory: 159808kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 120ms
memory: 159848kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"