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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#617478 | #8339. Rooted Tree | lzy | WA | 0ms | 3608kb | C++14 | 745b | 2024-10-06 15:48:42 | 2024-10-06 15:48:42 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define IOS ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
const int N = 1e6 + 5;
int a[N];
int mod=1e9+9;
int qpow(int a,int b){
int 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;
// cout<<34*qpow(3,mod-2)%mod<<"&\n";
ll leave=0,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";
// cout<<siz1<<" "<<siz2<<"&\n";
}
signed main() {
IOS;
int t = 1;
// cin>>t;
while (t--) {
solve();
}
}
Details
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Test #1:
score: 0
Wrong Answer
time: 0ms
memory: 3608kb
input:
6 2
output:
12
result:
wrong answer 1st numbers differ - expected: '18', found: '12'