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

#ifdef _RUTHEN
#include "debug.hpp"
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    ll N, VV, C;
    cin >> N >> VV >> C;
    V<ll> dp(VV + 1, 0);
    rep(i, N) {
        int v, w;
        cin >> v >> w;
        for (int j = VV; j >= 0; j--) {
            if (j + v <= VV) {
                dp[j + v] = max(dp[j + v], dp[j] + w + C);
            }
        }
        for (int j = 0; j <= VV; j++) {
            if (j + v <= VV) {
                dp[j + v] = max(dp[j + v], dp[j] + w);
            }
        }
    }
    cout << *max_element(dp.begin(), dp.end()) << '\n';
    return 0;
}