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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#694010#6736. Alice and BobNULL_SFTL 945ms69220kbC++23748b2024-10-31 17:07:222024-10-31 17:07:22

Judging History

你现在查看的是最新测评结果

  • [2024-10-31 17:07:22]
  • 评测
  • 测评结果:TL
  • 用时:945ms
  • 内存:69220kb
  • [2024-10-31 17:07:22]
  • 提交

answer

#include <iostream>

using namespace std;

const int mod=998244353;

int pre[10000001],inv[10000001];

inline int quick_pow(int base,int index)
{
	long long ans=1,tmp=base;
	
	while(index){
		if(index&1){
			ans*=tmp;
			ans%=mod;
		}
		tmp*=tmp;
		tmp%=mod;
		index>>=1;
	}
	
	return ans;
}

int get_inv(int x)
{
	return quick_pow(x,mod-2);
}

int get_CC(int down,int up)
{
	return 1ll*pre[down]*inv[down-up]%mod;
}

signed main()
{
	int n;
	cin>>n;
	
	pre[0]=inv[0]=1;
	for(int i=1;i<=n;i++){
		pre[i]=1ll*pre[i-1]*i%mod;
		inv[i]=1ll*inv[i-1]*get_inv(i)%mod;
	}
	
	int ans=0;
	for(int i=1;i<=(n+1)/2;i++){
		ans+=1ll*pre[n-i]*get_CC(n-i,i-1)%mod;
		ans%=mod;
	}
	
	cout<<ans;
	
	return 0;
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 5672kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5604kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5692kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 5632kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 5704kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 5692kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 1ms
memory: 5680kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 1ms
memory: 5684kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 1ms
memory: 5732kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 1ms
memory: 5680kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 1ms
memory: 5680kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 5680kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 5564kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 156ms
memory: 15656kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 876ms
memory: 64208kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 945ms
memory: 69220kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 692ms
memory: 55220kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 410ms
memory: 32140kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 812ms
memory: 60868kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 333ms
memory: 29344kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: -100
Time Limit Exceeded

input:

9999998

output:


result: