#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
int N, M, S;
cin >> N >> M >> S;
vector<int> A(N), B(N);
for (int i = 0; i < N; i++) {
cin >> A[i] >> B[i];
}
vector<int> o(N);
iota(o.begin(), o.end(), 0);
sort(o.begin(), o.end(), [&](int x, int y) {
return A[x] - B[x] > A[y] - B[y];
});
vector<ll> pf(N + 1), sf(N + 1);
priority_queue<pair<int, int>> Q;
ll sum_a = 0, sum_b = 0;
for (int i = 0; i < N; i++) {
Q.push({-A[o[i]], i});
sum_a += A[o[i]];
while (int(Q.size()) > M) {
sum_a -= A[o[Q.top().second]];
Q.pop();
}
pf[i + 1] = sum_a;
}
Q = priority_queue<pair<int, int>>();
for (int i = N - 1; i >= 0; i--) {
Q.push({-B[o[i]], i});
sum_b += B[o[i]];
while (int(Q.size()) > S) {
sum_b -= B[o[Q.top().second]];
Q.pop();
}
sf[i] = sum_b;
}
ll answer = numeric_limits<int>::min();
for (int i = 0; i <= N; i++) {
answer = max(answer, pf[i] + sf[i]);
}
cout << answer << "\n";
}
