#include <bits/stdc++.h>

typedef long long ll;

using namespace std;

const int N = 1e4 + 10;

ll dp[2][N];
ll max_k[N];
priority_queue<ll, vector<ll>, greater<ll>> big;//小根堆

struct gem{
	ll v; //value
	ll w; //weight
};

bool cmp(gem x, gem y)
{
	if(x.w == y.w) return x.v < y.v;
	else return x.w < y.w;
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);

	ll n, W, k;
	cin >> n >> W >> k;

	vector<gem> g(n);

	for(int i = 0; i < n; i ++) {
		// int tw, tv;
		cin >> g[i].w >> g[i].v;
	}

	sort(g.begin(), g.end(), cmp);

	// for(int i = 0; i < g.size(); i ++) {
	// 	cout << g[i].w << ' ' << g[i].v << endl;
	// }cout << endl;

	ll sum = 0;
	for(int i = n - 1; i >= n - k; i --) {
		sum += g[i].v;
		big.push(g[i].v);
	}
	// cout << big.top() << endl;

	ll index = n - k;

	max_k[index --] = sum;

	for(int i = n - k - 1; i >= 0; i --) {
		// cout << index << ' ';
		ll t = big.top();
		big.pop();
		if(g[i].v > t) {
			big.push(g[i].v);
			sum += g[i].v - t;
		} else big.push(t);

		max_k[index --] = sum;
	}

	int old = 1, now = 0;
	ll ans = 0;
	for(int i = 0; i < n - k; i ++) {
		swap(old, now);
		// cout << old << now << endl;
		for(int j = 0; j <= W; j ++) {
			if(g[i].w > j) dp[now][j] = dp[old][j];
			else dp[now][j] = max(dp[old][j], dp[old][j - g[i].w] + g[i].v);
		}
		// cout << dp[now][W] << endl;
		ans = max(ans, dp[now][W] + max_k[i + 1]);
	}

	cout << ans << endl;

}