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ID	Problem	Submitter	Result	Time	Memory	Language	File size	Submit time	Judge time
#97520	#5817. 小学生数学题	sichengzhou	60	638ms	142192kb	C++14	791b	2023-04-17 04:52:54	2023-04-17 04:52:55

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你现在查看的是最新测评结果

[2023-08-10 23:21:45]
System Update: QOJ starts to keep a history of the judgings of all the submissions.

[2023-04-17 04:52:55]
评测

测评结果：60
用时：638ms
内存：142192kb

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[2023-04-17 04:52:54]
提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=2e7+7,mod=998244353;
int n,m;
int p[N],tp;
int pd[N];
LL val[N];
LL ksm(LL x,int y)
{
	LL ret=1;
	while(y)
	{
		if(y&1)
		{
			ret=ret*x%mod;
		}
		x=x*x%mod;
		y>>=1;
	}
	return ret;
}
int main()
{
	scanf("%d%d",&n,&m);
	for(int i=2;i<=n;i++)
	{
		if(pd[i]==0)
		{
			p[++tp]=i;
		}
		for(int j=1;j<=tp&&(LL)p[j]*i<=n;j++)
		{
			pd[p[j]*i]=p[j];
			if(i%p[j])
			{
				break;
			}
		}
	}
	LL cur=1,ans=0;
	for(int i=1;i<=n;i++)
	{
		cur*=i;cur%=mod;
		if(pd[i]==0)
		{
			val[i]=ksm(i,mod-1-m);
		}else{
			val[i]=val[i/pd[i]]*val[pd[i]]%mod;
		}
	//	cout<<cur<<' '<<val[i]<<endl;
		ans+=cur*val[i]%mod;
		ans%=mod;
	}
	printf("%lld\n",ans);
	return 0;
}

Source code, Language: C++14

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 10

Accepted

time: 629ms

memory: 133964kb

input:

9450395 1

output:

688545438

result:

ok single line: '688545438'

Test #2:

score: 10

Accepted

time: 622ms

memory: 127900kb

input:

8978812 1

output:

334565356

result:

ok single line: '334565356'

Test #3:

score: 10

Accepted

time: 585ms

memory: 127376kb

input:

8944235 1

output:

982802915

result:

ok single line: '982802915'

Test #4:

score: 10

Accepted

time: 485ms

memory: 103592kb

input:

7081118 3

output:

599009773

result:

ok single line: '599009773'

Test #5:

score: 10

Accepted

time: 533ms

memory: 113120kb

input:

7904241 3

output:

871243720

result:

ok single line: '871243720'

Test #6:

score: 10

Accepted

time: 638ms

memory: 142192kb

input:

9921275 3

output:

549818101

result:

ok single line: '549818101'

Test #7:

score: 0

Time Limit Exceeded

input:

17575748 14135489

output:

result:

Test #8:

score: 0

Time Limit Exceeded

input:

19858362 14822524

output:

result:

Test #9:

score: 0

Time Limit Exceeded

input:

18848696 15530895

output:

result:

Test #10:

score: 0

Time Limit Exceeded

input:

17787945 13890407