#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int, int> pii;
const int N = 5e3 + 5, M = 1e4 + 5;
const int mod = 1e9 + 7;
const int inf = 0x3f3f3f3f3f3f3f3f;

int n, m, k;
int w[N], v[N], dp[M], pre[M];
bool vis[N];
void solve()
{
    cin >> n >> m >> k;
    for (int i = 1; i <= n; i++)
    {
        cin >> w[i] >> v[i];
    }
    for (int i = 1; i <= n; i++)
    {
        for (int j = m; j >= w[i]; j--)
        {
            if (dp[j] < dp[j - w[i]] + v[i])
            {
                pre[j] = i;
                dp[j] = max(dp[j], dp[j - w[i]] + v[i]);
            }
        }
    }

    // cout << "dp[m] = " << dp[m] << endl;

    int j = m;
    while (j > 0 && pre[j] > 0)
    {
        vis[pre[j]] = true;
        j = j - w[pre[j]];
        // cout << "j = " << j << endl;
    }
    // cout << "-------------" << endl;
    vector<int>sum;
    for (int i = 1; i <= n; i++)
    {
        if (!vis[i])
            sum.push_back(v[i]);

        // cout << "i = " << i << endl;
    }
    sort(sum.begin(), sum.end(), [&](int x, int y) {return x > y;});
    int ans = dp[m];
    for (int i = 0; i < min((int)(sum.size()), k); i++)
    {
        ans += sum[i];
    }
    cout << ans << endl;
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int test = 1;
    // cin >> test;
    for (int i = 1; i <= test; i++)
    {
        solve();
    }
    return 0;
}