#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vmi = vector<mint>;
using vvmi = vector<vmi>;
using vvvmi = vector<vvmi>;
#define all(a) (a).begin(), (a).end()
#define rep2(i, m, n) for (int i = (m); i < (n); ++i)
#define rep(i, n) rep2(i, 0, n)
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)

void solve(){
    
}
using p = pair<ll, ll>;

int main(){
    ll n, w; cin >> n >> w;
    vector<p> vp(n);
    rep(i, n){
        ll a, b; cin >> a >> b;
        vp[i] = {a, b};
    }

    sort(all(vp), [](const p a, const p b){
        if(a.first*b.second != a.second*b.first){
            return a.first*b.second > a.second*b.first;
        }else{
            return a.second < b.second;
        }
    });
    
    ll nw = w;
    ll ans = 0;
    if(w > 1000000){
        auto [a, b] = vp[0];
        ll c = (nw-1000000)/b;
        ans += a*c;
        nw -= b*c;
    }
    vvll dp(n, vll(nw+1, -1));
    for(int j = 0; j*vp[0].second <= nw; j++)dp[0][j*vp[0].second] = vp[0].first * j;
    rep2(i, 1, n){
        auto [a, b] = vp[i];
        rep(j, nw+1){
            if(dp[i-1][j] != -1)dp[i][j] = dp[i-1][j];
            if(j - b >= 0){
                if(dp[i][j-b] != -1)dp[i][j] = max(dp[i][j], dp[i][j-b] + a);
            }
        }
    }
    ll tmp = 0;
    rep(i, nw+1)tmp = max(tmp, dp[n-1][i]);
    cout << ans+tmp << endl;
    return 0;
}