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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#617519#8339. Rooted TreelzyTL 138ms3576kbC++14670b2024-10-06 15:59:062024-10-06 15:59:07

Judging History

你现在查看的是最新测评结果

  • [2024-10-06 15:59:07]
  • 评测
  • 测评结果:TL
  • 用时:138ms
  • 内存:3576kb
  • [2024-10-06 15:59:06]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
const int N = 1e6 + 5;
typedef long long ll;
#define IOS ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
int a[N];
int mod=1e9+9;
int qpow(ll a,ll b){
	ll res=1;
	while(b){
		if(b&1)res=res*a%mod;
		a=a*a%mod;
		b>>=1;
	}
	return res;
}
void solve() {
	int n,k;
	cin>>n>>k;
	ll av,sum=0;
	ll leave=0;int siz1=1,siz2=1;
	for(int i=1;i<=k;i++){
		av=leave*qpow(siz2,mod-2)%mod;
		sum=(sum+n*(av+1)%mod)%mod;
		leave=(leave+n*(av+1)%mod-av+mod)%mod;
		siz1=(siz1+n)%mod;
		siz2=(siz2+n-1)%mod;
	}
	cout<<sum<<"\n";
}
signed main() {
	IOS;
	int t = 1;
	while (t--) {
		solve();
	}
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3548kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3576kb

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 138ms
memory: 3548kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: -100
Time Limit Exceeded

input:

48 6713156

output:

198541581

result: