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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#89280#5817. 小学生数学题cyl00180 990ms236748kbC++14800b2023-03-19 15:24:362023-03-19 15:24:38

Judging History

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.
  • [2023-03-19 15:24:38]
  • 评测
  • 测评结果:80
  • 用时:990ms
  • 内存:236748kb
  • [2023-03-19 15:24:36]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
const int N = 2e7 + 5,p = 998244353;
int n,k,tot,sum,inv[N],fac[N],mi[N],pr[N];
bool f[N];
int ksm(int x,int y)
{
	int ret = 1;
	while(y)
	{
		if(y & 1) ret = 1LL * ret * x % p;
		x = 1LL * x * x % p;
		y >>= 1;
	}
	return ret;
}
int main()
{
	scanf("%d%d",&n,&k);
	inv[1] = fac[1] = mi[1] = sum = 1;
	for(int i = 2;i <= n;i++)
	{
		inv[i] = p - 1LL * (p / i) * inv[p % i] % p;
		fac[i] = 1LL * fac[i - 1] * i % p;
		if(!f[i])
		{
			mi[i] = ksm(inv[i],k);
			pr[++tot] = i;
		}
		sum = (sum + 1LL * fac[i] * mi[i] % p) % p;
		for(int j = 1;j <= tot && pr[j] * i <= n;j++)
		{
			mi[i * pr[j]] = 1LL * mi[i] * mi[pr[j]] % p;
			f[i * pr[j]] = 1;
			if(i % pr[j] == 0) break;
		}
	}
	printf("%d\n",sum);
	return 0;
}

Details

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Test #1:

score: 10
Accepted
time: 427ms
memory: 132548kb

input:

9450395 1

output:

688545438

result:

ok single line: '688545438'

Test #2:

score: 10
Accepted
time: 350ms
memory: 125664kb

input:

8978812 1

output:

334565356

result:

ok single line: '334565356'

Test #3:

score: 10
Accepted
time: 360ms
memory: 127668kb

input:

8944235 1

output:

982802915

result:

ok single line: '982802915'

Test #4:

score: 10
Accepted
time: 279ms
memory: 102028kb

input:

7081118 3

output:

599009773

result:

ok single line: '599009773'

Test #5:

score: 10
Accepted
time: 313ms
memory: 111652kb

input:

7904241 3

output:

871243720

result:

ok single line: '871243720'

Test #6:

score: 10
Accepted
time: 434ms
memory: 137876kb

input:

9921275 3

output:

549818101

result:

ok single line: '549818101'

Test #7:

score: 10
Accepted
time: 970ms
memory: 235804kb

input:

17575748 14135489

output:

69236780

result:

ok single line: '69236780'

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: 10
Accepted
time: 990ms
memory: 236748kb

input:

17787945 13890407

output:

989967864

result:

ok single line: '989967864'