#include <fstream>

using namespace std;

ifstream fin ("rucsac.in");
ofstream fout ("rucsac.out");

int n, g, i, v[10005], d[50005], j, m, p[10005];

int main()
{
    fin >> n >> g;
    for (i=1; i<=n; i++){
        fin >> v[i] >> p[i];
    }
    d[0] = 1;
    for (i=1; i<=n; i++){
        for (j=g; j>=0; j--){
            if (d[j] != 0 && j + v[i] <= g){
                d[j + v[i]] = max (d[j+v[i]], p[i] + d[j]);
            }
        }
    }
    for (i=0; i<=g; i++){
        m = max(m, d[i]);
    }
    fout << m - 1;
    return 0;
}