#include <fstream>
using namespace std;
ifstream in("rucsac.in");
ofstream out("rucsac.out");
static int p[5002],profit[10002],g[5002];
int main() {
    int n,k;
    in>>n>>k;
    for(int i=0;i<n;i++) {
        in >> g[i];
        in>>p[i];
    }
    for(int j=1;j<=k;j++)
        profit[j]=-1;
    profit[0]=0;
    for(int i=0;i<n;i++)
    {
        for(int j=k-g[i];j>=0;j--)
        {
            if(profit[j]!=-1 && profit[j]+p[i]>profit[j+g[i]])
            {
                profit[j+g[i]]=profit[j]+p[i];
            }
        }
    }
    int rasp=-1;
    for(int j=1;j<=k;j++)
        rasp=max(rasp,profit[j]);
    out<<rasp;
    return 0;
}