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: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i = 0; i < n; i++)
#define REP(i,n) for(int i = 1; i < n; i++)
#define per(i,n) for(int i = n-1; i >= 0; i--)
#define PER(i,n) for(int i = n; i >= 1; i--)
#define sz(x) int(x.size())
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define YesorNo(a) printf(a ? "Yes\n" : "No\n")
#define endl '\n'
#define fi first
#define se second
using ll = long long;
using P = pair<int,int>;
using Pl = pair<ll,ll>;
using vi = vector<int>;
using vii = vector<vi>;
using vl = vector<ll>;
using vll = vector<vl>;
using vs = vector<string>;
using vb = vector<bool>;
using vc = vector<char>;
using vcc = vector<vc>;
using vP = vector<P>;
using vPl = vector<Pl>;
const int dx[] = {0,1,0,-1,1,1,-1,-1};
const int dy[] = {1,0,-1,0,1,-1,-1,1};
const int inf = (1<<30)-1;
const ll infll = (1LL<<62)-1;
ll ceil(const ll &a, const ll &b){return ((a)+(b)-1)/b;}
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }


int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int n, max_w;
  cin >> n >> max_w;
  vii v(4);
  int w_s, a;
  cin >> w_s >> a;
  v[0].push_back(a);
  REP(i,n) {
    int w, b;
    cin >> w >> b;
    v[w-w_s].push_back(b);
  }
  rep(i,4) sort(rall(v[i]));
  int ans = 0;
  rep(i,sz(v[0])+1) {
    rep(j,sz(v[1])+1) {
      rep(k,sz(v[2])+1) {
        rep(l,sz(v[3])+1) {
          int tmp = 0;
          int weight = i*(w_s) + j*(w_s+1) + k*(w_s+2) + l*(w_s+3);
          if(weight > max_w) continue;
          rep(cnt,i) tmp += v[0][cnt];
          rep(cnt,j) tmp += v[1][cnt];
          rep(cnt,k) tmp += v[2][cnt];
          rep(cnt,l) tmp += v[3][cnt];
          chmax(ans, tmp);
        }
      }
    }
  }
  cout << ans << endl;
}