#include <bits/stdc++.h>
using namespace std;
const long long inf = -1e18;
const int mxN = 2e5 + 10;
const int mxM = 505;
vector<int> adj[mxN];
long long dp1[mxN][mxM], dp2[mxM], val[mxN];
int n, m, root = 0;
void dfs(int u){
for(int j = 1; j <= m + 1; ++j) dp1[u][j] = inf, dp2[j] = inf;
for(auto it : adj[u]) {
dfs(it);
for(int x = 0; x <= m; ++x){
for(int y = 0; y <= m; ++y){
if((x + y) > m) break;
dp2[x + y] = max(dp2[x + y], dp1[u][x] + dp1[it][y]);
}
}
for(int j = 0; j <= m; ++j){
dp1[u][j] = dp2[j];
}
}
dp1[u][1] = max(dp1[u][1], val[u]);
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
cin >> n >> m;
for(int i = 1, u; i <= n; ++i){
cin >> u >> val[i];
adj[u].push_back(i);
if(u == 0) root = i;
}
dfs(root);
cout << dp1[root][m] << "\n";
return 0;
}
