#include <bits/stdc++.h>

using namespace std;

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

int N, G, k = 1;
int p[10001], g[10001], dp[2][10001];

int main()
{
    fin >> N >> G;

    for(int i = 1; i <= N; i++)
    {
        fin >> g[i] >> p[i];
    }

    for(int j = 0; j <= G; j++)
    {
        dp[0][j] = -1;
        dp[1][j] = -1;
    }

    dp[0][0] = 0;

    for(int i = 1; i <= N; i++)
    {
        for(int j = 1; j <= G; j++)
        {
            if(dp[1-k][j - g[i]] != -1 && j - g[i] >= 0)
            {
                dp[k][j] = max(dp[1-k][j], dp[1-k][j - g[i]] + p[i]);
            }
            else
            {
                dp[k][j] = dp[1-k][j];
            }
        }

        k ? k -= 1 : k += 1;
    }

    fout << dp[k-1][G];

    return 0;
}