#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cmath>
#include <tuple>
#include <bitset>
#include <map>
#include <set>
#include <queue>
#include <iomanip>

#define rep(i,n) for(i=0; i<n; ++i)
#define inc_rep(i,a,n) for(i=a; i<=n; ++i)
#define dec_rep(i,n,a) for(i=n; i>=a; --i)
#define in(a) cin >> a
#define out(a,b) cout << a << b
#define print_vec(v) for(auto it=v.begin();it!=v.end();++it)cout<<*it <<" ";cout<<endl
#define print_vec2d(v) for(int i=0;i<v.size();++i){for(int j=0;j<v[i].size();++j)cout<<v[i][j]<<" ";cout<<endl;}cout<<endl
using namespace std;
using lint = long long;

void func(vector<bool> &v, vector<lint> &d, int j, int si, int ai, int m){
    if(d[j]==0) return;
    if(j+si>m) return;
    if(v[j]) return;
    if(d[j+si]>d[j]+ai) return;
    else{
        func(v, d, j+si, si, ai, m);
        d[j+si]=d[j]+ai;
        v[j+si]=true;
    }
    return;
}

int main(void){
    int i, j;
    lint k, cnt=0, x, y;
    lint p, q, n, m;
    string s;
    in(n);in(m);
    vector<pair<lint, lint> > v(n);
    rep(i,n){
        lint a, b;
        in(a);in(b);
        v[i]=make_pair(a, b);
    }
    vector<lint> d(m+1, 0);
    rep(i, n){
        // print_vec(d);
        lint si, ai;
        tie(si, ai) = v[i];
        if(si<=m){
            vector<bool> f(m+1, false);
            rep(j,m+1){
                func(f, d, j, si, ai, m);
            }
            if(d[si]<ai){
                d[si]=ai;
                f[si]=true;
            }
        }
    }
    out(*max_element(d.begin(), d.end()),endl);
    // print_vec(d);
    return 0;
}