//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
//#pragma GCC optimize("unroll-loops")
/*#pragma GCC optimize("section-anchors")
#pragma GCC optimize("profile-values,profile-reorder-functions,tracer")
#pragma GCC optimize("vpt")
#pragma GCC optimize("rename-registers")
#pragma GCC optimize("move-loop-invariants")
#pragma GCC optimize("unswitch-loops")
#pragma GCC optimize("function-sections")
#pragma GCC optimize("data-sections")
#pragma GCC optimize("branch-target-load-optimize")
#pragma GCC optimize("branch-target-load-optimize2")
#pragma GCC optimize("btr-bb-exclusive")*/
//#pragma comment(linker, "/STACK:367077216")
#define _CRT_SECURE_NO_WARNINGS
#include <chrono>
#include <set>
#include <map>
#include <deque>
#include <string>
#include <cstdint>
#include <cmath>
#include <queue>
#include <cassert>
#include <random>
#include <bitset>
#include <iomanip>
#include <numeric>
#include <time.h>//////////////
#include <ctime>
#include <string>
#include <cstdio>
#include <vector>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
//++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++
//#define endl '\n'
#define mp make_pair
#define pbc push_back
#define pob pop_back()
#define empb emplace_back
#define queuel queue<long long>
#define sqr(a) ((a) * (a))
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pin(p) cin >> p.first >> p.second;
#define uniq(a) sort(all(a));(a).resize(unique(all(a)) - a.begin());
#define rev(v) reverse(v.begin(), v.end());
#define sout(s, c) for (auto i : s) cout << i << c;
#define pout(p) cout << p.first << " " << p.second;
#define er(v, l, r) erase(v.begin() + l, v.begin() + r);
#define vin(v) for (ll i = 0; i < v.size(); ++i) cin >> v[i];
#define vout(v, c) for (int i = 0; i < v.size(); ++i) cout << v[i] << c;
#define pushi(v, a) for (int i = 0; i < a.size(); ++i) v.push_back(a[i]);
#define fastio() ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0); srand(time(NULL))
#define dab(v) for(auto i:v)cout<<i<<' ';
#define sp system("pause")
//++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++
using namespace std;
//++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
//++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++--++
const ld EPS = 0.001;
const ld EPS2 = 1e-6;
const ld PI = acos(-1);
const int MOD7 = 1000000007;
const int MOD9 = 1000000009;
const int a228 = 18;
const int inf = 1e9;
const ll kekmod = 1791791791;
const ll bestmod = 1148822869;
const int mod = MOD7;
signed main()
{
	fastio();
	ll n, w;
	cin >> n >> w;
	vector<pair<int, int>> a(n);
	for (int i = 0; i < n; ++i) cin >> a[i].first >> a[i].second;
	auto ta = a;
	sort(all(ta), [&](pair<int, int> a, pair<int, int> b) { return a.second > b.second; });
	ll ans = 0;
	for (int take = 1; take <= n; ++take)
	{
		ll tw = w - 1ll * a[0].first * take;
		if (tw < 0) break;
		if (take * 3 <= tw)
		{
			ll now = 0;
			for (int i = 0; i < take; ++i)now += ta[i].second;
			ans = max(ans, now);
		}
		else
		{
			vector<vector<vector<ll>>> dp(n + 1, vector<vector<ll>>(take + 1, vector<ll>(tw + 1)));
			dp[0][0][0] = 0;
			for (int i = 0; i < n; ++i)
			{
				for (int tkn = 0; tkn <=min(i,take-1) ; ++tkn)
				{
					for (int ttw = 0; ttw <= tw; ++ttw)
					{
						dp[i + 1][tkn][ttw] = max(dp[i + 1][tkn][ttw], dp[i][tkn][ttw]);
						if (ttw + a[i].first - a[0].first <= tw)
						{
							dp[i + 1][tkn+1][a[i].first - a[0].first + ttw] = max(dp[i + 1][tkn+1][a[i].first -a[0].first+ ttw], dp[i][tkn][ttw] + a[i].second);
						}
					}
				}
			}
			for (int i = 1; i <= n; ++i) for (int j = 0; j <= tw; ++j) ans = max(ans, dp[i][take][j]);
		}
	}
	cout << ans;
//	sp;
}

Measured memory_bytes: 2560