#include <bits/stdc++.h>
using namespace std;
// #define int long long
constexpr int maxn = 300001;
int n, m, a[maxn], siz[maxn];
vector<int> dp[maxn], adj[maxn];
int sizfind(int v) {
siz[v] = 1;
for (int u : adj[v]) siz[v] += sizfind(u);
return siz[v];
}
void dfs(int v) {
vector<int> ret;
ret.resize(m + 5, 0);
for (int u : adj[v]) {
dfs(u);
for (int j = 0; j <= min(siz[u], m); j++) {
for (int k = 0; k + j <= min(m, siz[v]); k++) {
dp[v][j + k] = max(dp[v][j + k], ret[k] + dp[u][j]);
}
}
ret = dp[v];
}
dp[v][1] = max(dp[v][1], a[v]);
for (int i = 0; i <= min(siz[v], m); i++) dp[v][i] = max(dp[v][i], ret[i]);
return;
}
signed main()
{
cin.tie(0) -> sync_with_stdio(0);
cin >> n >> m;
int rt = 0;
for (int i = 1; i <= n; i++) {
int p, x; cin >> p >> x;
a[i] = x;
if (!p) {rt = i; continue;}
adj[p].push_back(i);
}
for (int i = 1; i <= n; i++) dp[i].resize(m + 5, 0);
for (int i = 1; i <= n; i++) dp[i][0] = 0;
sizfind(rt);
dfs(rt);
cout << dp[rt][m];
}
