#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;
#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
int n, k;
vector<int> vect, sz;
vector<vector<int> > graph, dp;
void dfs(int node){
sz[node]=1;
dp[node].resize(k+1, 0);
for (auto num:graph[node]){
dfs(num);
for (int i=k; i>=0; --i)for (int j=min(i, sz[num]); j>=0; --j)dp[node][i]=max(dp[node][i], dp[num][j]+dp[node][i-j]);
sz[node]+=sz[num];
dp[num].clear();
}
dp[node][1]=max(dp[node][1], vect[node]);
}
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int root, a;
cin>>n>>k;
sz.resize(n+1);
graph.resize(n+1);
vect.resize(n+1);
for (int i=1; i<=n; ++i){
cin>>a>>vect[i];
if (!a)root=i;
else graph[a].pb(i);
}
dfs(root);
cout<<dp[root][k];
}
