#include <bits/stdc++.h>
#define DIM 200010
#define DIMM 510
using namespace std;
vector <int> L[DIM];
int dp[DIM][DIMM],v[DIM],cnt[DIM],aux[DIM];
int n,m,i,x,rad;
void dfs (int nod){
for (auto vecin : L[nod]){
dfs (vecin);
cnt[nod] += cnt[vecin];
}
if (L[nod].empty()) /// frunza
cnt[nod] = 1;
for (auto vecin : L[nod]){
for (int i=1;i<=cnt[nod];i++)
aux[i] = 0;
for (int i=1;i<=cnt[vecin];i++) /// cat elimin din subarborele asta
for (int j=cnt[nod];j>=i;j--)
aux[j] = max (aux[j],dp[nod][j-i] + dp[vecin][i]);
for (int i=1;i<=cnt[nod];i++)
dp[nod][i] = max (dp[nod][i],aux[i]);
}
dp[nod][1] = max(dp[nod][1],v[nod]);
}
int main (){
//ifstream cin ("date.in");
//ofstream cout ("date.out");
cin>>n>>m;
for (i=1;i<=n;i++){
cin>>x>>v[i];
if (x)
L[x].push_back(i);
else rad = i;
}
dfs (rad);
cout<<dp[rad][m];
return 0;
}
