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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#276681#6736. Alice and Bobucup-team958#AC ✓121ms81812kbC++14685b2023-12-06 08:01:112023-12-06 08:01:11

Judging History

你现在查看的是最新测评结果

  • [2023-12-06 08:01:11]
  • 评测
  • 测评结果:AC
  • 用时:121ms
  • 内存:81812kb
  • [2023-12-06 08:01:11]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
const int mod=998244353;
const int maxn=10000010;
int n,ans;
int fac[maxn],ifac[maxn];
int fpow(int n,int m,int x=1){
	for(;m;m>>=1,n=1ll*n*n%mod)
		if(m&1) x=1ll*x*n%mod;
	return x; 
}
int C(int n,int m){
	if(n<0||m<0||n-m<0) return 0;
	return 1ll*fac[n]*ifac[m]%mod*ifac[n-m]%mod;
}
void init(int n){
	fac[0]=ifac[0]=1;
	for(int i=1;i<=n;i++)
		fac[i]=1ll*fac[i-1]*i%mod;
	ifac[n]=fpow(fac[n],mod-2);
	for(int i=n-1;i;i--)
		ifac[i]=1ll*ifac[i+1]*(i+1)%mod; 
}
int main(){
	scanf("%d",&n),init(n);
	for(int i=1;i<=n;i++)
		ans=(ans+1ll*C(n-i,i-1)*fac[i-1]%mod*fac[n-i])%mod;
	printf("%d\n",ans);	
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 3628kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 3572kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3540kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

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

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 3636kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3636kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3876kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3824kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3880kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3636kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3876kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 3644kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3884kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 22ms
memory: 14464kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 113ms
memory: 62928kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 109ms
memory: 67460kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 87ms
memory: 51604kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 47ms
memory: 31160kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 100ms
memory: 58076kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 37ms
memory: 26444kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 117ms
memory: 81700kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 121ms
memory: 81688kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 121ms
memory: 81812kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"