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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#417359#6736. Alice and Bobericmegalovania#AC ✓650ms81296kbC++201.3kb2024-05-22 17:55:462024-05-22 17:55:47

Judging History

你现在查看的是最新测评结果

  • [2024-05-22 17:55:47]
  • 评测
  • 测评结果:AC
  • 用时:650ms
  • 内存:81296kb
  • [2024-05-22 17:55:46]
  • 提交

answer

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

//#define ONLINE
#ifndef ONLINE
#define debug(...) fprintf(stderr,##__VA_ARGS__)
#else
#define debug(...) ;
#endif

using LL=long long;
using PII=pair<int,int>;

template<typename T>
inline T READ(){
	T x=0; bool f=0; char c=getchar();
	while(!isdigit(c)) f|=(c=='-'),c=getchar();
	while(isdigit(c)) x=x*10+c-'0',c=getchar();
	return f?-x:x;
}
inline int read(){return READ<int>();}
inline LL readLL(){return READ<LL>();}
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

const int mod=998244353;
LL ksm(LL a,LL b){
	a%=mod; LL ret=1;
	while(b){
		if(b&1) ret=ret*a%mod;
		a=a*a%mod;
		b>>=1;
	}
	return ret;
}

namespace Fac{//factorial
	vector<LL>fc;
	void init(int N){
		fc.resize(N);
		fc[0]=1;
		for(int i=1;i<N;i++){
			fc[i]=fc[i-1]*i%mod;
		}
	}
	LL F(const int& x){
		return fc[x];
	}
	LL P(const int& x,const int& y){
		if(y>x) return 0;
		return fc[x]*ksm(fc[x-y],mod-2)%mod;
	}
}

int main(){
	int n=read(); LL ans=0;
	Fac::init(n+1);
	for(int i=1;i<=n;i++){
		ans=(ans+(Fac::P(n-i,i-1)*Fac::F(n-i)%mod))%mod;
	}
	printf("%lld",ans);
	return 0;
}

/* stuff you should look for
* int overflow, array bounds
* special cases (n=1?)
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3640kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3788kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3836kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 3708kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3808kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3820kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3684kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3672kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 1ms
memory: 3704kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 1ms
memory: 3824kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3844kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 3748kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 1ms
memory: 3648kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 82ms
memory: 13932kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 489ms
memory: 62560kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 524ms
memory: 66628kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 397ms
memory: 51204kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 227ms
memory: 30500kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 445ms
memory: 57388kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 186ms
memory: 25784kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 650ms
memory: 81144kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 646ms
memory: 81296kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 647ms
memory: 81184kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"