import java.util.Scanner;
import java.lang.Math;

public class Main{
    private static final int N = 1010;
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int m = sc.nextInt();

        int[] v = new int[N];
        int[] w = new int[N];

        for(int i=1;i<=n;i++){
            v[i] = sc.nextInt();
            w[i] = sc.nextInt();
        }

        int[][] dp = new int[N][N];
        for(int i=1;i<=n;i++){
            for(int j=0;j<=m;j++){
                for(int k=0;k*v[i]<=j;k++){
                    dp[i][j] = Math.max(dp[i][j],dp[i][j-k*v[i]]+k*w[i]);
                }
            }
        }

        System.out.println(dp[n][m]);
    }
}