#include <iostream>
#include <fstream>

using namespace std;

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

int g, w, dp[1001][10001];

struct
{
    int q, c;
}v[1001];

int main()
{
    fin >> g >> w;
    for(int i = 1; i <= g; i++)
        fin >> v[i].q >> v[i].c;
    for(int i = 1; i <= g; i++)
        for(int j = 1; j <= w; j++)
            if(v[i].q <= j && v[i].c + dp[i - 1][j - v[i].q] > dp[i - 1][j])
                dp[i][j] = v[i].c + dp[i - 1][j - v[i].q];
            else
                dp[i][j] = dp[i - 1][j];
    fout << dp[g][w];

    return 0;
}