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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
#760018#6736. Alice and Bobship2077AC ✓109ms81956kbC++23696b2024-11-18 14:06:452024-11-18 14:06:49

Judging History

你现在查看的是最新测评结果

  • [2024-11-18 14:06:49]
  • 评测
  • 测评结果:AC
  • 用时:109ms
  • 内存:81956kb
  • [2024-11-18 14:06:45]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
constexpr int M=1e7+5,mod=998244353;
int n,ans,fac[M],ifac[M];
int read(){
	int x=0;char ch=getchar();
	while (!isdigit(ch)) ch=getchar();
	while (isdigit(ch)) x=x*10+ch-48,ch=getchar();
	return x;
}
int qpow(int x,int n){
	int s=1; while (n){
		if (n&1) s=1ll*s*x%mod;
		x=1ll*x*x%mod; n>>=1;
	} return s;
}
void init(int n){
	for (int i=fac[0]=1;i<=n;i++) fac[i]=1ll*fac[i-1]*i%mod;
	ifac[n]=qpow(fac[n],mod-2);
	for (int i=n;i;i--) ifac[i-1]=1ll*ifac[i]*i%mod;
}
int main(){
	n=read();init(n);
	for (int i=1;(i<<1)-1<=n;i++)
		ans=(ans+1ll*fac[n-i]*ifac[n-(i<<1)+1]%mod*fac[n-i])%mod;
	printf("%d\n",ans);
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 5824kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5772kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5820kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 5808kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 5840kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5768kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 5756kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 5820kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 5820kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 5896kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 5832kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 5824kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 1ms
memory: 5840kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 13ms
memory: 15640kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 89ms
memory: 64984kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 83ms
memory: 69248kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 72ms
memory: 52724kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 38ms
memory: 35876kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 69ms
memory: 61272kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 34ms
memory: 27708kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 93ms
memory: 81904kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 109ms
memory: 81816kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 101ms
memory: 81956kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"