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)

// {{{
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <sstream>
#include <queue>
#include <deque>
#include <bitset>
#include <iterator>
#include <list>
#include <stack>
#include <map>
#include <set>
#include <functional>
#include <numeric>
#include <utility>
#include <limits>
#include <time.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>

using namespace std;

typedef long int i32;
typedef unsigned long int u32;
typedef long long int i64;
typedef unsigned long long int  u64;
typedef pair<i32, i32> PII;
typedef vector<i32> VI;
typedef vector<string> VS;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef map<i32, i32> MPII;
typedef set<i32> SETI;
typedef multiset<i32> MSETI;
#define IN(x) cin >> x;
#define SCD(t) scanf("%d",&t)
#define SCLD(t) scanf("%ld",&t)
#define SCLLD(t) scanf("%lld",&t)
#define SCC(t) scanf("%c",&t)
#define SCS(t) scanf("%s",t)
#define SCF(t) scanf("%f",&t)
#define SCLF(t) scanf("%lf",&t)
#define MEM(a, b) memset(a, (b), sizeof(a))
#define ZERO(a) memset(a, 0, sizeof(a))
#define FOR(i, j, k, in) for (int i=j ; i<k ; i+=in)
#define RFOR(i, j, k, in) for (int i=j ; i>=k ; i-=in)
#define REP(i, j) FOR(i, 0, j, 1)
#define RREP(i, j) RFOR(i, j, 0, 1)
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define FOREACH(it, l) for (auto it = l.begin(); it != l.end(); it++)
#define BTW(A, B, C) assert( B <= A && A <= C)
#define MP make_pair
#define PB push_back
#define PF push_front
#define INF (int)1e9
#define EPS 1e-9
#define PI 3.1415926535897932384626433832795
#define MOD 1000000007
#define DEBUG(x) cout << #x << ": " << x << endl;

template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }
// }}}

const u64 MAX_N = 1000;
const u64 MAX_W = (u64)1e9;
array<u64, MAX_N> w, v;
u64 dp[MAX_N][4 * MAX_N + 1];
// u64 dp[4 * MAX_N + 1][MAX_N];
int main() {
    u64 N, W;
    cin >> N >> W;
    REP(i, N) {
        cin >> w[i] >> v[i];
    }
    const u64 minW = *min_element(w.begin(), w.end());
    REP(i, N) {
        w[i] -= minW;
    }
    u64 ans = 0;
    dp[0][0] = 0;
    REP(i, N)REP(j, 4 * MAX_N + 1) {
        dp[i][j] = 0;
    }
    REP(i, N)RREP(j, N)REP(k, 4 * N + 1) {
        if((u64)k + w[i] + minW * (u64)(j + 1) <= W) {
            amax(dp[j+1][k+w[i]], dp[j][k]+v[i]);
            // DEBUG(dp[j][k+w[i]]);
            amax(ans, dp[j+1][k+w[i]]);
        }
    }
    cout << ans << endl;

    return 0;
}