#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstring>
#include<vector>
#include <algorithm>
using namespace std;
const int N = 2e2+20, M = 1e2+10, mod = 1e9+7, inf = 1e9+1000;
typedef long long ll;

int n,m,v[N],f[N],dp[N][N],p[N];
vector<int > G[N];
int siz[N];
void dfs(int u) {
    siz[u] = 1;
    dp[u][1] = v[u];
    int totson = G[u].size();
    for(int i=0;i<G[u].size();i++) {
        int to = G[u][i];
        dfs(to);
        siz[u] += siz[to];
    }
    for(int j=0;j<totson;j++) {
        int v = G[u][j];
        for(int i=siz[u];i>=1;i--) {
            for(int k=1;k<i&&k<=siz[u];k++) {
                dp[u][i] =  max(dp[v][k]+dp[u][i-k] , dp[u][i]);
            }
        }
    }
}
int main() {
    while(~scanf("%d%d",&n,&m)) {
        if(!n&&!m) break;
        int cnt = 0;
        for(int i=0;i<N;i++) G[i].clear();
        memset(dp,0,sizeof(dp));
        memset(f,0,sizeof(f));
        for(int i=1;i<=n;i++) {
            int a,b;
            scanf("%d%d",&a,&v[i]);
            if(a == 0) {p[++cnt] = i;continue;}
            G[a].push_back(i);
        }
        for(int i=1;i<=cnt;i++) dfs(p[i]);
        for(int i=1;i<=cnt;i++) {
            for(int x=m;x>=1;x--)
            for(int j=0;j<=siz[p[i]]&&j<=x;j++) {
                f[x] = max(f[x-j] + dp[p[i]][j],f[x]);
            }
        }
        printf("%d\n",f[m]);

    }
}