#include <iostream>
#include <fstream>

using namespace std;

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

#define lim 10010
int n,dp[lim],gmax,g,p,rez=-1;

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

    fin.close();
    fout.close();
    return 0;
}