#include <bits/stdc++.h>

using namespace std;
ifstream fin("energii.in");
ofstream fout("energii.out");

int g, w, e, c, dp[2][5001], L;
int main()
{
    fin >> g >> w;
    L = 1;
    for(int i = 1; i <= g; ++i, L = 1 - L)
    {
        fin >> e >> c;
        for(int j = 0; j <= w; ++j)
        {
            dp[L][j] = dp[1 - L][j];
            if(j >= e)
                dp[L][j] = max(dp[L][j], dp[1 - L][j - e] + c);
        }
    }
    L = 1 - L;
    int sol = 0;
    for(int i = 1; i <= w; ++i)
        sol = max(sol, dp[L][i]);
    fout << sol;
    return 0;
}