#include <stdio.h>
#include <stdlib.h>
#define N 5000
#define K 10000

int g[N],p[N],profit[K],n,k;

int max(int a, int b)
{
    if(a>b)
    {
        return a;
    }
    return b;
}
int main()
{
    freopen("rucsac.in","r",stdin);
    freopen("rucsac.out","w",stdout);
    scanf("%d%d",&n,&k);
    int i,j, rez=-1;
    for(j=1;j<=k;j++)
    {
        profit[j]=-1;
    }

    for(i=0;i<n;i++)
    {
        int g,p;
        scanf("%d%d",&g,&p);
        for(j=k-g;j>=0;j--)
        {
            if(profit[j]!=-1)
            {
                profit[j+g]=max(profit[j+g],profit[j]+p);
            }
        }
    }
    for(j=1;j<=k;j++)
    {
        rez=max(rez,profit[j]);
    }
    printf("%d",rez);
    return 0;
}