#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//const long nPrime = 1000000007;
//const long nPrime = 998244353;
typedef long long ll;
int main() {
    ll n,u,c;
    cin >> n >> u >> c;
    vector<vector<ll>> vviDP(u+1,vector<ll>(2,0)), vviPrev(u+1,vector<ll>(2,0));
    for(ll i = 1; i <= n; i++){
        ll v,w;
        cin >> v >> w;
        for(ll j = 0; j <= u; j++){
            vviDP[j][0] = max(vviPrev[j][0], vviPrev[j][1]);
        }
        for(ll j = v; j <= u; j++){
            vviDP[j][1] = max(vviDP[j-v][0]+w+c, vviDP[j-v][1]+w);
        }
        vviPrev = vviDP;
    }

    ll nAns = 0;
    for(ll i = 0; i <= u; i++){
        nAns = max(nAns, vviDP[i][0]);
        nAns = max(nAns, vviDP[i][1]);
    }
    
    cout << nAns << endl;
    return 0;
}