Problem:
Score : 400 points

Problem Statement

You have N items and a bag of strength W.
The i-th item has a weight of w_i and a value of v_i.

You will select some of the items and put them in the bag.
Here, the total weight of the selected items needs to be at most W.

Your objective is to maximize the total value of the selected items.

Constraints

1 ≤ N ≤ 100

1 ≤ W ≤ 10^9

1 ≤ w_i ≤ 10^9

For each i = 2,3,...,N, w_1 ≤ w_i ≤ w_1 + 3.

1 ≤ v_i ≤ 10^7

W, each w_i and v_i are integers.

Input

Input is given from Standard Input in the following format:

N W
w_1 v_1
w_2 v_2
:
w_N v_N

Output

Print the maximum possible total value of the selected items.

Sample Input 1

4 6
2 1
3 4
4 10
3 4

Sample Output 1

11

The first and third items should be selected.

Sample Input 2

4 6
2 1
3 7
4 10
3 6

Sample Output 2

13

The second and fourth items should be selected.

Sample Input 3

4 10
1 100
1 100
1 100
1 100

Sample Output 3

400

You can take everything.

Sample Input 4

4 1
10 100
10 100
10 100
10 100

Sample Output 4

0

You can take nothing.

Solution in C++14 (GCC 5.4.1) (judge verdict: Runtime Error)

//#pragma once
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <iostream>
#include <queue>
#include <algorithm>
#include <sstream>
#include <vector>
#include <math.h>
#include <set>
#include <map>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cctype>
#include <cstdlib>      // srand,rand
#include <random>
#include <functional>

using namespace std;
#define ll long long
#define lp(i,n) for(ll i=0;i<n;i++)

#define modd 1000000007
#define mod2 998244353

#define INF 8223372036854775807ll
#define ALL(a)  (a).begin(),(a).end()


typedef pair<long long, long long> pl;
typedef pair<double, double> pd;
typedef pair<ll, string> pls;



typedef string::const_iterator State;
class ParseError {};



/*
class SegmentTree {



private:

	ll cont_num = 2;
	pd initial_v;
	vector<pd> dat;


public:


	SegmentTree() {};


	void init(ll size, double initial_value_first, double initial_value_second) {

		cont_num = 2;
		initial_v.first = initial_value_first;
		initial_v.second = initial_value_second;

		while (cont_num < size) {
			cont_num *= 2;
		}

		dat.resize(2 * cont_num);//サイズ設定

		for (int i = 0; i < 2 * cont_num; i++)dat[i] = initial_v;//初期化



	}


	void Update(ll position, double value_f, double value_s) {



		ll k = cont_num + position;

		dat[k].first = value_f;
		dat[k].second = value_s;

		while (k > 1) {
			k /= 2;
			dat[k].first = dat[k * 2 + 1].first * dat[k * 2].first;
			dat[k].second = dat[k * 2 + 1].first * dat[k * 2].second + dat[k * 2 + 1].second;


		}


	}

	/*
	ll query_proces(ll a, ll b, ll k, ll l, ll r) {

		if (r <= a || b <= l)return initial_v;

		if (a <= l && r <= b)return dat[k];
		else {
			ll vl = query_proces(a, b, k * 2, l, (l + r) / 2);
			ll vr = query_proces(a, b, k * 2 + 1, (l + r) / 2, r);
			return min(vl, vr);
		}

	}


	ll query(ll left, ll right) {
		return query_proces(left, right, 1, 0, cont_num);
	}
	*/
	/*
		double query() {
			return dat[1].first + dat[1].second;
		}

	};*/


template <typename T>
class Zip {
	vector<T> d;
	bool flag;
	void init() {
		sort(d.begin(), d.end());
		d.erase(unique(d.begin(), d.end()), d.end());
		flag = false;
	}
public:
	Zip() {
		flag = false;
	}
	void add(T x) {
		d.push_back(x);
		flag = true;
	}
	ll getNum(T x) {
		if (flag) init();
		return lower_bound(d.begin(), d.end(), x) - d.begin();
	}
	ll size() {
		if (flag) init();
		return (ll)d.size();
	}
};


ll N, M, K, a, b, c, d, e, H, W, L, T;
ll x, y, z;
ll A[2000004] = {};
ll B[2000004] = {};
ll C[2000004] = {};
ll D[1000006] = {};
ll E[1000006] = {};
bool f;
string S[200000];
string SS;
set <long long>sll;
pl bufpl;
vector <long long>vl[200005];
vector <long long>vll;
vector <long long>v;
vector <pl>vpl;
vector <string> vs;
set<ll> llset;
set<string> Sset;
multiset<ll> llmset;
queue<ll> ql;
multiset<pl> plmset;


typedef struct ST
{
	ll first;
	ll second;
	ll cost;

	bool operator<(const ST& another) const
	{
		return cost < another.cost;//比較
	};

	bool operator>(const ST& another) const
	{
		return cost > another.cost;//比較
	};

}ST;
//queue<ST> qst;
priority_queue<ST, vector<ST>, greater<ST> > qst;



/*vector <ST> vst;
ST st[200005];
ST bufst;
bitset<5000> bits;*/


long long modinv(long long aa, long long mm) {
	long long bb = mm, uu = 1, vv = 0;
	while (bb) {
		long long tt = aa / bb;
		aa -= tt * bb; swap(aa, bb);
		uu -= tt * vv; swap(uu, vv);
	}
	uu %= mm;
	if (uu < 0) uu += mm;
	return uu;
}





ll zettai(ll aa) {

	if (aa < 0) {
		aa *= -1;
	}
	return aa;

}

float zettai(float aa) {

	if (aa < 0) {
		aa *= -1;
	}
	return aa;

}


/*
class UnionFind
{

public:


	vector <ll>pairent;
	vector <ll>depth;
	vector <ll>size;


	UnionFind(ll Amount) : pairent(Amount, 1), depth(Amount, 1), size(Amount, 1) {

		for (ll i = 0; i < Amount; i++) {
			pairent[i] = i;
		}


	}


	ll FindPairent(ll x) {
		if (pairent[x] == x)return x;
		else return pairent[x] = FindPairent(pairent[x]);

	}


	ll Merge(ll x, ll y) {
		x = FindPairent(x);
		y = FindPairent(y);

		if (x != y) {
			if (depth[x] > depth[y]) {
				pairent[y] = pairent[x];
				return size[x] += size[y];
			}
			else {
				pairent[x] = pairent[y];
				if (depth[x] == depth[y]) {
					depth[y] ++;
				}

				return size[y] += size[x];
			}

		}
		else {
			return -1;
		}



	}



	bool IsSame(ll x, ll y) {
		if (FindPairent(x) == FindPairent(y))return true;
		else return false;
	}


	ll GetSize(ll x) {
		x = FindPairent(x);
		return size[x];
	}


};
*/

class UnionFind
{

public:

	vector <ll>pairent;
	vector <ll>depth;
	vector <ll>size;

	UnionFind(ll Amount) : pairent(Amount, 1), depth(Amount, 1), size(Amount, 1) {

		for (ll i = 0; i < Amount; i++) {
			pairent[i] = i;
		}
	}


	ll FindPairent(ll x) {
		if (pairent[x] == x)return x;
		else return pairent[x] = FindPairent(pairent[x]);
	}


	ll Merge(ll x, ll y) {
		x = FindPairent(x);
		y = FindPairent(y);

		if (x != y) {
			if (depth[x] > depth[y]) {
				pairent[y] = pairent[x];
				return size[x] += size[y];
			}
			else {
				pairent[x] = pairent[y];
				if (depth[x] == depth[y]) {
					depth[y] ++;
				}
				return size[y] += size[x];
			}
		}
		else {
			return -1;
		}
	}



	bool IsSame(ll x, ll y) {
		if (FindPairent(x) == FindPairent(y))return true;
		else return false;
	}


	ll GetSize(ll x) {
		x = FindPairent(x);
		return size[x];
	}


};

struct Edge
{
	ll a, b, cost;


	bool operator<(const Edge& other) const {
		return cost < other.cost;
	}
};

struct Graph
{
	ll n;  // 頂点数
	vector<Edge> es;  // 辺集合
};

class Kruskal {

	Graph origin_G;
	Graph MST;
	ll total_cost = 0;

public:

	void Solve() {
		UnionFind uf = UnionFind(MST.n);
		for (ll i = 0; i < origin_G.es.size(); i++) {
			ll a = origin_G.es[i].a;
			ll b = origin_G.es[i].b;
			ll cost = origin_G.es[i].cost;

			if (!uf.IsSame(a, b)) {
				uf.Merge(a, b);
				MST.es.push_back(origin_G.es[i]);
				total_cost += cost;
			}
		}
	}

	Kruskal(Graph graph) {
		origin_G = graph;
		MST = graph;
		MST.es.clear();
		sort(origin_G.es.begin(), origin_G.es.end());
	}

	ll GetMinCost() {
		return total_cost;
	}

};


ll RepeatSquaring(ll N, ll P, ll M) {
	if (P == 0) return 1;
	if (P % 2 == 0) {
		ll t = RepeatSquaring(N, P / 2, M) % M;
		return t * t % M;
	}
	return N * RepeatSquaring(N, P - 1, M) % M;
}

/*
ll KurikaesiNijou(ll a, ll b, ll P) {

	if (b == 0)return 1;
	if (b % 2 == 0) {
		ll c=KurikaesiNijou(a,b/2,P)%P;
		return c * c %P;
	}
	else {
		ll c = KurikaesiNijou(a, b/2, P) % P;
		return a * c * c % P;
	}

}*/




ll GCD(ll a, ll b) {
	if (a % b == 0)return b;
	else return GCD(b, a % b);
}

ll Min(ll a, ll b) {
	if (a < b)return a;
	else return b;
}

ll Max(ll a, ll b) {
	if (a > b)return a;
	else return b;
}

ll Sum(ll a, ll b) {
	return a + b;
}

template <typename T>
class SegmentTree {
	ll n;
	vector<T> node;
	function<T(T, T)> fun, fun2;
	bool customChange;
	T outValue, initValue;
public:
	void init(ll num, function<T(T, T)> resultFunction, T init, T out, function<T(T, T)> changeFunction = NULL) {
		// changeFunction: (input, beforevalue) => newvalue
		fun = resultFunction;
		fun2 = changeFunction;
		customChange = changeFunction != NULL;
		n = 1;
		while (n < num) n *= 2;
		node.resize(2 * n - 1);
		fill(node.begin(), node.end(), init);
		outValue = out;
		initValue = init;
	}
	void valueChange(ll num, T value) {
		num += n - 1;
		if (customChange) node[num] = fun2(value, node[num]);
		else node[num] = value;
		while (num > 0) num = (num - 1) / 2, node[num] = fun(node[num * 2 + 1], node[num * 2 + 2]);
	}
	T rangeQuery(ll a, ll b, ll l = 0, ll r = -1, ll k = 0) { // [a, b)
		if (r == -1) r = n;
		if (a <= l && r <= b) return node[k];
		if (b <= l || r <= a) return outValue;
		ll mid = (l + r) / 2;
		return fun(rangeQuery(a, b, l, mid, 2 * k + 1), rangeQuery(a, b, mid, r, 2 * k + 2));
	}
};




class Combination {

	vector<ll> factorial;
	vector<ll> factorial_inv;
	ll mod;
	ll max_n;


public:
	void Init(ll init_max_n, ll init_mod) {
		max_n = init_max_n;
		mod = init_mod;
		factorial.resize(max_n + 1);
		factorial[0] = 1;
		for (ll i = 1; i < factorial.size(); i++) {
			factorial[i] = factorial[i - 1] * i;
			factorial[i] %= mod;
		}

		factorial_inv.resize(max_n + 1);
		factorial_inv[0] = 1;
		for (ll i = 1; i < factorial_inv.size(); i++) {
			factorial_inv[i] = factorial_inv[i - 1] * modinv(i, mod);
			factorial_inv[i] %= mod;
		}
	}



	ll GetComb(ll n, ll k) {
		ll comb = factorial[n];
		comb *= factorial_inv[k];
		comb %= mod;
		comb *= factorial_inv[n - k];
		comb %= mod;
		return comb;
	}

	ll GetH(ll n, ll k) {//n+k-1<=max_N
		ll comb = factorial[n + k - 1];
		comb *= factorial_inv[n];
		comb %= mod;
		comb *= factorial_inv[k - 1];
		comb %= mod;
		return comb;
	}

};



class Tree {

	ll node_N;
	vector<ll> node;
	vector<vector<pl>> pass;
	ll diameter = -1;
	vector<ll> dist_Diamieter[2];

	pl maxDist_Num;

public:


	void Init(ll node_Num) {
		node_N = node_Num;
		node.resize(node_N + 1);
		pass.resize(node_N + 1);

		dist_Diamieter[0].resize(node_N + 1);
		lp(i, node_N + 1)dist_Diamieter[0][i] = -1;
		dist_Diamieter[1].resize(node_N + 1);
		lp(i, node_N + 1)dist_Diamieter[1][i] = -1;
	}

	void AddEdge(ll a, ll b, ll dist) {
		bufpl.first = b;
		bufpl.second = dist;
		pass[a].push_back(bufpl);
		bufpl.first = a;
		pass[b].push_back(bufpl);
	}


	void DFS(ll step, ll now, ll dist) {

		dist_Diamieter[step][now] = dist;
		if (dist_Diamieter[step][now] > maxDist_Num.first) {
			maxDist_Num.first = dist_Diamieter[step][now];
			maxDist_Num.second = now;
		}

		for (ll i = 0; i < pass[now].size(); i++) {
			ll next_node = pass[now][i].first;
			if (dist_Diamieter[step][next_node] == -1) {
				DFS(step, next_node, dist + pass[now][i].second);
			}
		}
	}

	ll GetDiameter(ll min_node_num) {
		if (diameter >= 0)return diameter;
		else {
			maxDist_Num.first = -1;
			maxDist_Num.second = -1;
			DFS(0, min_node_num, 0ll);
			ll step2_start = maxDist_Num.second;

			maxDist_Num.first = -1;
			maxDist_Num.second = -1;
			DFS(1, step2_start, 0ll);

			diameter = maxDist_Num.first;
			return diameter;
		}
	}

	ll GetDistFromMinNode(ll num) {
		return dist_Diamieter[0][num];
	}

};


void Nibu(ll node, ll co) {

	C[node] = co % 2;
	D[co % 2]++;

	lp(i, vl[node].size()) {
		ll next = vl[node][i];
		if (C[next] == -1) {
			Nibu(next, co + 1);
		}
	}

}

ll dp[105][105][305] = {};

int main() {

	cin >> N >> W;
	lp(i, N)cin >> A[i] >> B[i];

	lp(i, N) {
		lp(j, 301)lp(k, 301)dp[i][j][k] = dp[i - 1][j][k];
		
		if (i == 0) {
			if (A[i] > W) {
				cout << 0 << endl;
				return 0;
			}
			else {
				for (ll j = 0; j <= 300; j++)dp[i][1][j] = B[i];
			}
		}
		else {
			A[i] -= A[0];
			for (ll j = 0; j <= 300 - A[i]; j++) {
				for (ll k = 0; k <= i; k++) {
					dp[i][k+1][j + A[i]] = max(dp[i][k+1][j + A[i]], dp[i - 1][k][j] + B[i]);
				}
			}
		}
	}
	ll ans = 0;

	lp(i, N+1) {
		e = min(300ll, W - A[0]*i);
		if (e < 0)break;
		ans = max(ans, dp[N-1][i][e]);
	}
	cout << ans << endl;

	//cout << fixed << setprecision(12) << bb << endl;
	return 0;

}