#include <bits/stdc++.h>
using namespace std;
const int M = 505;
const int maxn = 2e5 + 5;
int n, m;
int sz[maxn];
int val[maxn];
int dp[maxn][M];
vector<int>adj[maxn];
void calcsz(int v, int p){
for(int i : adj[v]){
if(i == p) continue;
calcsz(i, v);
sz[v] += sz[i];
}
sz[v] += adj[v].size();
}
void dfs(int v, int p){
int tmp[m + 5] = {};
int cnt = 0;
for(int i : adj[v]){
if(i == p) continue;
dfs(i, v);
cnt++;
for(int j = 1; j <= min(m, sz[v]); j++){
for(int k = 0; k <= min(j, sz[i]); k++){
int l = j - k;
dp[v][j] = max(dp[i][k] + tmp[l], dp[v][j]);
}
}
for(int j = 1; j <= min(m, sz[v]); j++) tmp[j] = dp[v][j];
}
dp[v][1] = max(dp[v][1], val[v]);
}
signed main()
{
cin.tie(0) -> sync_with_stdio(0);
cin >> n >> m;
int rt;
for(int i = 1; i <= n; i++){
int p, w;
cin >> p >> w;
if(p == 0) rt = i;
val[i] = w;
adj[i].push_back(p);
adj[p].push_back(i);
}
calcsz(rt, 0);
dfs(rt, 0);
cout << dp[rt][m];
}
