#include <bits/stdc++.h>
#define nmax 10005

using namespace std;

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

int dp[nmax / 2][nmax], n, g, gr, p;

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