#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define ll long long

// Knapsack function to maximize beauty within a budget
ll knapsack(int W, const vector<pair<int, int>>& items) {
    vector<ll> dp(W + 1, 0); // dp[w] represents max beauty for budget w

    for (const auto& [price, beauty] : items) { 
        for (int w = W; w >= price; --w) {
            dp[w] = max(dp[w], dp[w - price] + beauty);
        }
    }

    return dp[W];
}

int main() {
    int n, W, k;
    cin >> n >> W >> k;

    vector<pair<int, int>> gemstones(n); // {price, beauty}
    for (int i = 0; i < n; ++i) {
        cin >> gemstones[i].first >> gemstones[i].second;
    }

    ll maxBeauty = 0;
    for (int mask = 0; mask < (1 << n); ++mask) {
        if (__builtin_popcount(mask) == k) { // Check if subset size is exactly k
            ll freeBeauty = 0, freeCost = 0;
            vector<pair<int, int>> remainingGemstones;

            for (int i = 0; i < n; ++i) {
                if (mask & (1 << i)) {
                    freeBeauty += gemstones[i].second; // Take this gemstone for free
                } else {
                    remainingGemstones.push_back(gemstones[i]); // Add to items to buy
                }
            }

            // Use knapsack to find max beauty for remaining gemstones
            ll currentBeauty = freeBeauty + knapsack(W, remainingGemstones);
            maxBeauty = max(maxBeauty, currentBeauty);
        }
    }

    cout << maxBeauty << endl;

    return 0;
}