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

typedef long long ll;

const int N = 5005;
const int M = 1e4 + 5;

struct node {
	ll w, v;

	node() {}
	node(ll w, ll v): w(w), v(v) {}
} a[N];

ll n, W, k, ans, f[N][M];

priority_queue <ll, vector <ll>, greater <ll> > Q;

int main() {
	#ifdef LOCAL
		assert(freopen("test.in", "r", stdin));
		assert(freopen("test.out", "w", stdout));
	#endif
	ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
	cin >> n >> W >> k;
	for (int i = 1; i <= n; ++i) {
		cin >> a[i].w >> a[i].v;
	}
	sort(a + 1, a + n + 1, [](node x, node y) {
		return x.v < y.v;
	});
	for (int i = 1; i <= n; ++i) {
		for (int j = a[i].w; j <= W; ++j) {
			f[i][j] = max(f[i - 1][j], f[i - 1][j - a[i].w] + a[i].v);
		}
		for (int j = 1; j <= W; ++j) {
			f[i][j] = max(f[i][j], f[i][j - 1]);
		}
	}
	ll sum = 0;
	for (int i = n; i >= n - k + 1; --i) {
		Q.push(a[i].w);
		sum += a[i].v;
	}
	ans = sum + f[n - k][W];
	for (int i = n - k; i; --i) {
		sum += a[i].v;
		Q.push(a[i].w);
		W -= Q.top();
		Q.pop();
		if (W < 0) {
			break;
		}
		ans = max(ans, sum + f[i - 1][W]);
	}
	cout << ans << "\n";
	return 0;
}