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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
#372551#6736. Alice and BobQian#AC ✓109ms159900kbC++14831b2024-03-31 15:20:572024-03-31 15:20:58

Judging History

你现在查看的是最新测评结果

  • [2024-03-31 15:20:58]
  • 评测
  • 测评结果:AC
  • 用时:109ms
  • 内存:159900kb
  • [2024-03-31 15:20:57]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int long long
#define dd double
#define rep(i, a, b) for (int i = a; i <= b; i++)
#define pii pair<int, int>
#define Mod 998244353
int power(int x,int y){
	if(y==0)return 1;
	int sum=power(x,y>>1);
	if(y&1)return sum*sum%Mod*x%Mod;
	  else return sum*sum%Mod;
}
const int N=1e7+10;
int n,fac[N],inv[N];
void solve()
{
	int ans=0;cin>>n;
	fac[0]=1;
	for(int i=1;i<=n;i++)
	  fac[i]=fac[i-1]*i%Mod;
	inv[n]=power(fac[n],Mod-2);
	for(int i=n-1;i>=0;i--)
	  inv[i]=inv[i+1]*(i+1)%Mod;
	for(int i=1;i<=(n+1)/2;i++){
		ans=(ans+fac[n-i]*fac[n-i]%Mod*inv[n-2*i+1]%Mod)%Mod;
	}
	cout << ans << endl;
}

signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);
	int _ = 1;
	while (_--)
		solve();
    return 0;
}

詳細信息

Test #1:

score: 100
Accepted
time: 1ms
memory: 5596kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5660kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5656kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 2ms
memory: 7708kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 5704kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5596kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 1ms
memory: 5660kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 5660kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 1ms
memory: 5664kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 1ms
memory: 5672kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 1ms
memory: 5696kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 5664kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 5668kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 13ms
memory: 27332kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 68ms
memory: 126256kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 47ms
memory: 134316kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 55ms
memory: 101140kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 39ms
memory: 61888kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 57ms
memory: 113788kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 20ms
memory: 50948kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 106ms
memory: 159856kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 107ms
memory: 159860kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 109ms
memory: 159900kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"