#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ll mask){return __builtin_ctzll(mask);}
int logOf(ll mask){return __lg(mask);}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b) {a = b; return true;}
return false;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b) {a = b; return true;}
return false;
}
template <class T>
void printArr(T& container, string separator = " ", string finish = "\n"){
for(auto item: container) cout << item << separator;
cout << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const int N = 2e5 + 69, M = 501, INF = 1e9 + 69;
int n, k;
int a[N];
vector<int> graph[N];
int l[N], topo[N], dfs_cnt = 0;
void dfs(int u){
l[u] = INF;
for(int v: graph[u]) {
dfs(v);
minimize(l[u], l[v]);
}
topo[++dfs_cnt] = u;
minimize(l[u], dfs_cnt);
}
int dp[N][M], ma_dp[N][M];
void solve(){
cin >> n >> k;
for(int i = 1; i <= n; ++i){
int j; cin >> j >> a[i];
graph[j].push_back(i);
}
dfs(0);
for(int i = 0; i <= n; ++i) for(int j = 0; j <= k; ++j) ma_dp[i][j] = dp[i][j] = -INF;
dp[0][0] = ma_dp[0][0] = 0;
for(int i = 1; i <= n; ++i){
for(int j = 1; j <= k; ++j) {
maximize(dp[i][j], ma_dp[l[topo[i]]-1][j-1] + a[topo[i]]);
}
for(int j = 0; j <= k; ++j) {
ma_dp[i][j] = max(ma_dp[i-1][j], dp[i][j]);
}
}
cout << ma_dp[n][k] << "\n";
}
int main(void){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
clock_t start = clock();
solve();
cerr << "Time elapsed: " << clock() - start << "ms!\n";
return 0;
}
