#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n, w; cin >> n >> w;
	vector<long long>a(n), b(n);// value/weight
	rep(i, n)cin >> a[i] >> b[i];
	{
		long long bestv = a[0], bestw = b[0];
		long long maxw = b[0];
		rep2(i, 1, n) {
			if (bestv * b[i] < a[i] * bestw) {
				bestv = a[i];
				bestw = b[i];
			}
			chmax(maxw, b[i]);
		}
		vector<long long> dp(bestw * maxw + 1, -LINF);
		dp[0] = 0;
		rep(i, dp.size()) {
			rep(j, n) {
				int ni = i + b[j];
				if (ni >= dp.size())continue;
				chmax(dp[ni], dp[i] + a[j]);
			}
		}
		long long ans = 0;
		rep(i, n) {
			rep(j, dp.size()) {
				if (j > w)break;
				long long x = (w - j) / b[i];
				chmax(ans, dp[j] + x * a[i]);
			}
		}
		cout << ans << endl;
	}
	/*int sz = 0;
	rep(i, n)sz += 1000 * b[i];
	vector<long long>dp(sz + 1, -LINF);
	dp[0] = 0;
	rep(i, n) {
		int vv = a[i], ww = b[i];
		rep(j, dp.size()) {
			int nj = j + b[i];
			if (nj >= dp.size())break;
			chmax(dp[nj], dp[j] + a[i]);
		}
	}
	long long ans = 0;
	rep(i, n) {
		rep(j, dp.size()) {
			if (j > w)break;
			long long x = (w - j) / b[i];
			chmax(ans, dp[j] + x * a[i]);
		}
	}
	cout << ans << endl;*/
	return 0;
}