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

int n, m, k;
int dp[5005][10005];
struct node {int w, v;} a[5005];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<>> q;
long long sum, ans;

int main() {
	scanf("%d%d%d", &n, &m, &k);
	for (int i = 1; i <= n; i++) scanf("%d%d", &a[i].w, &a[i].v);
	sort(a + 1, a + n + 1, [](const node &x, const node &y) {return x.v > y.v;});
	for (int i = n; i >= 1; i--) {
		for (int j = 0; j < a[i].v; j++) dp[i][j] = dp[i + 1][j];
		for (int j = a[i].w; j <= m; j++)
			dp[i][j] = max(dp[i + 1][j], dp[i + 1][j - a[i].w] + a[i].v);
	}
	for (int i = 1; i <= k; i++) sum += a[i].v, q.emplace(a[i].w, i);
	ans = sum + dp[k + 1][m];
	for (int W = m, p = k; !q.empty() && W > 0; ) {
		int id = q.top().second;
		q.pop();
		if (a[id].w > W) break;
		W -= a[id].w;
		if (p < n) {
			p++;
			sum += a[p].v;
			q.emplace(a[p].w, p);
		}
		ans = max(ans, sum + dp[p + 1][W]);
	}
	printf("%lld\n", ans);
	return 0;
}