#include <bits/stdc++.h>
using namespace std;
int en[200001];
vector<int> adj[200001];
int cost[200001];
int n,m;int timer = 0;
vector<int> euler;
void dfs(int i,int pr){
++timer;
euler.push_back(i);
for(auto j:adj[i]){
if(j==pr)continue;
dfs(j,i);
}
en[i] = timer;
}
int dp[200001][501];
int solve(int i,int rem){
if(i==n)return (rem==0?0:-1e9);
if(dp[i][rem]!=-1)return dp[i][rem];
int c1 = solve(i+1,rem);
if(rem)c1 = max(c1,solve(en[euler[i]],rem-1)+cost[euler[i]]);
return dp[i][rem] = c1;
}
signed main(){
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
cin>>n>>m;
int ro = 0;
for(int i = 0;i<n;i++){
int a,b;
cin>>a>>b;
cost[i+1] = b;
if(a==0)ro = i+1;
else{
adj[a].push_back(i+1);
adj[i+1].push_back(a);
}
}
dfs(ro,0);
memset(dp,-1,sizeof dp);
cout<<solve(0,m)<<"\n";
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
156 ms |
397128 KB |
Output is correct |
2 |
Correct |
164 ms |
397116 KB |
Output is correct |
3 |
Correct |
140 ms |
397168 KB |
Output is correct |
4 |
Correct |
161 ms |
398108 KB |
Output is correct |
5 |
Correct |
172 ms |
398172 KB |
Output is correct |
6 |
Correct |
184 ms |
398156 KB |
Output is correct |
7 |
Correct |
1002 ms |
411628 KB |
Output is correct |
8 |
Correct |
1031 ms |
411552 KB |
Output is correct |
9 |
Correct |
1142 ms |
414448 KB |
Output is correct |
10 |
Correct |
1574 ms |
416212 KB |
Output is correct |