#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
using namespace std;
// using namespace __gnu_pbds;
// #define int long long
#define mod 1000000007
#define base 7001
#define base2 757
#define F first
#define S second
// #define pi acos(-1)
#define double long double
// #define ordered_set tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update>
// #define ordered_multiset tree<int, null_type, less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
// #pragma GCC optimize("O3,Ofast,unroll-loops")
// #pragma GCC target("avx2,sse3,sse4,avx")
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
constexpr int maxn = 300001;
const int N = 1 << (int)(ceil(log2(maxn)));
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);
}
if (adj[v].size()) ret = dp[adj[v][0]];
for (int i = 1; i < adj[v].size(); i++) {
int u = adj[v][i];
for (int j = 0; j <= min(siz[u], m); j++) {
for (int k = 0; k + j <= m && k + j <= siz[v]; k++) {
dp[v][j + k] = max(dp[v][j + k], ret[k] + dp[u][j]);
}
}
ret = dp[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, dp[i][1] = a[i];
sizfind(rt);
dfs(rt);
// for (int i = 1; i <= n; i++) {
// for (int j = 0; j <= m; j++) cout << dp[i][j] << ' ';
// cout << "\n";
// }
// for (int i = 1; i <= n; i++) cout << siz[i] << " ";
cout << dp[rt][m];
}
