#include <bits/stdc++.h>
#define rep(i, a, b) for(int i = (int)a; i <= (int)b; i ++)
#define per(i, a, b) for(int i = (int)a; i >= (int)b; i --)
#define ll long long
#define no { puts("No"); return; }
#define yes { puts("Yes"); return; }
using namespace std;
const int maxn = 5010;
int n, m, k;
ll dp[maxn][maxn * 2];
struct Data {
    int w, v;
    bool operator < (const Data & a) const {
        return v > a.v;
    }
} a[maxn];
bool cmp(Data x, Data y) { return x.w > y.w; }
void solve() {
    cin >> n >> m >> k;
    ll tot = 0, res = 0;
    rep(i, 1, n) cin >> a[i].w >> a[i].v;
    sort(a + 1, a + 1 + n, cmp);
    rep(i, 1, n + 1) rep(j, 0, m) dp[i][j] = 0;
    per(i, n, 1) rep(j, 0, m)
        if(j >= a[i].w) dp[i][j] = max(dp[i][j], dp[i + 1][j - a[i].w] + a[i].v);
    priority_queue < Data > pq;
    rep(i, 1, k) pq.push(a[i]), tot += a[i].v;
    res = tot;
    rep(i, k + 1, n) {
        res = max(res, dp[i][m] + tot);
        Data tmp = pq.top();
        if(a[i].v > tmp.v) {
            pq.pop();
            tot += a[i].v - tmp.v;
            pq.push(a[i]);
        }
    }
    cout << res << '\n';
}

int main() {
#ifdef LOCAL
    freopen("data.in", "r", stdin);
#endif
    ios :: sync_with_stdio(false);
    cin.tie(nullptr), cout.tie(nullptr);
    int T = 1;
    // cin >> T;
    while(T --) solve();
    return 0;
}