//
//  main.cpp
//  poj3624Cpp
//
//  Created by 韩雪滢 on 12/11/16.
//  Copyright ? 2016 韩雪滢. All rights reserved.
//

#include <iostream>
#include <algorithm>
using namespace std;

int main() {
    int N,M;
    cin >> N >> M;
    int *des = new int[M+1];
    for(int i=0;i<=M;i++)
        des[i] = 0;
    for(int j=0;j<N;j++){
        int w,d;
        cin >> w >> d;
        for(int k=M;k>0;k--)
        {
            if(k-w >= 0){
            des[k] = max(des[k],des[k-w]+d);
            }
        }
    }
    int result = 0;
    for(int n=1;n<=M;n++){
        if(des[n] > result)
            result = des[n];
    }
    cout << result << endl;
    return 0;
}