#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <string>
#include <map>
#include <stack>
#include <vector>
#include <set>
#include <queue>
#pragma comment (linker,"/STACK:102400000,102400000")
#define maxn 205
#define MAXN 1005
#define mod 1000000009
#define INF 0x3f3f3f3f
#define pi acos(-1.0)
#define eps 1e-6
typedef long long ll;
using namespace std;

int n,m,k,ans,cnt,tot,flag;
int pp[maxn],cost[maxn],dp[maxn][maxn];
struct Node
{
    int v,w,next;
} edge[MAXN];

void addedge(int u,int v,int w)
{
    cnt++;
    edge[cnt].v=v;
    edge[cnt].w=w;
    edge[cnt].next=pp[u];
    pp[u]=cnt;
}
void dfs(int u)
{
    int i,j,v,t;
    dp[u][1]=cost[u];
    for(i=pp[u]; i; i=edge[i].next)
    {
        v=edge[i].v;
        dfs(v);
        for(j=m; j>=0; j--)
        {
            t=0;
            for(k=0; k<=j-(u!=0); k++)
            {
                t=max(t,dp[v][k]+dp[u][j-k]);
            }
            dp[u][j]=max(dp[u][j],t);
        }
    }
}
int main()
{
    int i,j,t,u;
    while(scanf("%d%d",&n,&m),n|m)
    {
        cnt=0;
        memset(pp,0,sizeof(pp));
        for(i=1; i<=n; i++)
        {
            scanf("%d%d",&u,&cost[i]);
            addedge(u,i,0);
        }
        memset(dp,0,sizeof(dp));
        dfs(0);
        ans=dp[0][m];
        printf("%d\n",ans);
    }
    return 0;
}