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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#462381 | #8339. Rooted Tree | zttttt | TL | 214ms | 95848kb | C++14 | 1.2kb | 2024-07-03 18:34:59 | 2024-07-03 18:34:59 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=1e7+10,M=1e9+9;
int f[N],ny[N],dp[N],zt[N];
int ksm(int a,int b,int c){
int b1=b;
zt[1]=a%c;
int cnt=1;
int ans=1;
while(b1){
cnt++;
zt[cnt]=zt[cnt-1]*zt[cnt-1]%c;
b1/=2;
}
cnt=0;
while(b){
cnt++;
if(b&1){
//cnt++;
ans*=zt[cnt];
ans%=c;
}
b>>=1;
}
return ans;
}
signed main(){
int m,k;
cin>>m>>k;
f[0]=1;
int maxx=1;
for(int i=1;i<=k;i++){
f[i]=f[i-1]-1+m;
maxx=max(maxx,f[i]);
}
//for(int i=1;i<=k;i++)cout<<f[i]<<endl;
if(maxx>10000000)maxx=10000000;
dp[0]=0;
ny[1]=1;
for(int i=2;i<=maxx;i++){
ny[i]=(M-M/i)*ny[M%i]%M;
}
for(int i=1;i<=k;i++){
if(f[i]<=1e7){
dp[i]=((dp[i-1]*f[i-1])%M*ny[f[i]]%M-(dp[i-1]*ny[f[i]]%M)%M+M)%M+m*dp[i-1]%M*ny[f[i]]%M+m*ny[f[i]]%M;
dp[i]%=M;
}else{
int zqx=ksm(f[i],M-2,M);
dp[i]=((dp[i-1]*f[i-1])%M*zqx%M-(dp[i-1]*zqx%M)%M+M)%M+m*dp[i-1]%M*zqx%M+m*zqx%M;
dp[i]%=M;
}
}
//for(int i=1;i<=k;i++)cout<<dp[i]<<endl;
int ans1=dp[k]*f[k]%M;
for(int i=1;i<k;i++){
ans1=ans1+dp[i]%M;
ans1%=M;
}
cout<<ans1<<endl;
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 1ms
memory: 9676kb
input:
6 2
output:
18
result:
ok 1 number(s): "18"
Test #2:
score: 0
Accepted
time: 1ms
memory: 9756kb
input:
2 6
output:
600000038
result:
ok 1 number(s): "600000038"
Test #3:
score: 0
Accepted
time: 214ms
memory: 95848kb
input:
83 613210
output:
424200026
result:
ok 1 number(s): "424200026"
Test #4:
score: -100
Time Limit Exceeded
input:
48 6713156
output:
198541581