#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
istream &operator>>(istream &is, modint &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint &a) { return os << a.val(); }
istream &operator>>(istream &is, modint998244353 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint998244353 &a) { return os << a.val(); }
istream &operator>>(istream &is, modint1000000007 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint1000000007 &a) { return os << a.val(); } 

typedef long long ll;
typedef vector<vector<int>> Graph;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define FOR(i,l,r) for (int i = l;i < (int)(r); i++)
#define rep(i,n) for (int i = 0;i < (int)(n); i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define my_sort(x) sort(x.begin(), x.end())
#define my_max(x) *max_element(all(x))
#define my_min(x) *min_element(all(x))
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
const int INF = (1<<30) - 1;
const ll LINF = (1LL<<60) - 1;
const int MOD = 998244353;
const int MOD2 = 1e9+7;
const double PI = acos(-1);
vector<int> di = {1,0,-1,0};
vector<int> dj = {0,1,0,-1};

#ifdef LOCAL
#  include <debug_print.hpp>
#  define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define debug(...) (static_cast<void>(0))
#endif

// template<typename T>
// void subset_zeta_transform(vector<T> &d){
//     const int n2 = d.size();
//     assert((n2 & (n2 - 1)) == 0);

//     int n = 0;
//     while((1<<n)<n2) n++;

//     debug(d);
//     for(int S = 1; S < n2; S++){
//         for(int bit = 0; bit < n; bit++){
//             if((S >> bit) & 1){
//                 int subset = S & ~(1 << bit);
//                 // d[S] += d[subset];
//                 chmax(d[S], d[subset]);
//             }
//         }
//     }
//     debug(d);
// }

// https://ei1333.github.io/library/math/fft/subset-zeta-moebius-transform.hpp
template <typename T>
void subset_zeta_transform(vector<T> &f) {
  const int n = (int)f.size();
  assert((n & (n - 1)) == 0);
  for (int i = 1; i < n; i <<= 1) {
    for (int j = 0; j < n; j += i << 1) {
      for (int k = 0; k < i; k++) {
        // f[j + k + i] += f[j + k];
        chmax(f[j + k + i], f[j + k]);
      }
    }
  }
}

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    int N; cin >> N;
    int L = 1 << N;
    int mask = L - 1;

    ll M, Q; cin >> M >> Q;
    vector<ll> A(N), B(N);
    rep(i,N) cin >> A[i] >> B[i];

    // dp1[S] ... Sの部分集合で1日目の最大値
    vector<ll> dp1(L);
    rep(s,L){
        ll acc_a = 0, acc_b = 0;
        rep(bit,N)if((s>>bit)&1){
            acc_a += A[bit];
            acc_b += B[bit];
        }
        if(acc_a <= M) dp1[s] = acc_b;
    }
    subset_zeta_transform(dp1);
    // rep(s,L)rep(bit,N)if((~s>>bit)&1)chmax(dp1[s|(1<<bit)], dp1[s]);

    // dp2[S] ... Sの部分集合で2日目の最大値
    vector<ll> dp2(L);
    rep(s,L){
        ll acc_a = 0, acc_b = 0;
        rep(bit,N)if((s>>bit)&1){
            acc_a += A[bit];
            acc_b += B[bit];
        }
        if(acc_a <= Q) dp2[s] = acc_b;
    }
    subset_zeta_transform(dp2);
    // rep(s,L)rep(bit,N)if((~s>>bit)&1)chmax(dp2[s|(1<<bit)], dp2[s]);

    ll ans = 0;
    rep(s,L)chmax(ans, dp1[s] + dp2[mask ^ s]);
    cout << ans << endl;
}