#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
#define MAXN 300000
#define s second
#define f first
using namespace std;
int cities[MAXN + 1][2];
bool used[MAXN + 1]; // city used or not
vector<pair<int, pair<int, int>>> music;
vector<pair<int, pair<int, int>>> sports;
int N;
int mpos = N - 1;
int spos = N - 1;
void findM() {
while (used[music[mpos].s.s] && mpos != 0) mpos--;
}
void findS() {
while (used[sports[spos].s.s]) spos--;
}
int main() {
int M, S;
cin >> N >> M >> S;
for (int i = 0; i < N; i++) {
cin >> cities[i][0] >> cities[i][1];
music.push_back(make_pair(cities[i][0], make_pair(cities[i][1], i)));
sports.push_back(make_pair(cities[i][1], make_pair(cities[i][0], i)));
}
sort(music.begin(), music.end());
sort(sports.begin(), sports.end());
int ans = 0;
mpos = N - 1;
spos = N - 1;
while (M > 0) {
used[music[mpos].s.s] = true;
ans += music[mpos].f;
findM();
M--;
}
while (S > 0) {
int pos = sports[spos].s.s;
if (used[pos]) {
findM();
if (cities[pos][1]+music[mpos].f > cities[pos][0]) {
ans += cities[pos][1] + music[mpos].f - cities[pos][0];
used[music[mpos].s.s] = true;
spos--;
S--;
}
else {
spos--;
}
}
else {
ans += sports[spos].f;
used[sports[spos].s.s] = true;
spos--;
S--;
}
}
cout << ans;
}
