#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <vector>
#include <map>
#include <set>
#include <ctime>
#include <cassert>
#include <queue>

using namespace std;

#define f first
#define s second
#define mp make_pair
#define pb push_back
#define forit(it,con) for (typeof(con.begin()) it = con.begin(); it != con.end(); ++it)
#define f0(a) memset(a, 0, sizeof(a))
#define all(v) v.begin(), v.end()
#define pii pair<int,int>
#define vi vector<int>
#define ll long long
#ifdef WIN32
    #define I64 "%I64d"
#else
    #define I64 "%lld"
#endif
const int maxn = (int)1e6;
ll H[maxn];
int n, M, S;

pii a[maxn];

priority_queue<int, vector<int> , greater<int> > pq;
priority_queue<int> pqm;

int main() {

    scanf("%d%d%d", &n, &M, &S);
    for (int i = 0; i < n; ++i)  {
        int u, v;
        scanf("%d%d", &u, &v);
        a[i] = mp(u, v);
    }

    sort(a, a + n);
    reverse(a, a + n);

    ll ans = 0, sum = 0;

    for (int i = 0; i < M + S; ++i) {
        sum += a[i].s;

        if (pq.size() != M) {
            sum += a[i].f - a[i].s;
            pq.push(a[i].f - a[i].s);
        }
        else
        if (M > 0 && pq.top() < a[i].f - a[i].s) {
            sum -= pq.top();
            pq.pop();
            sum += a[i].f - a[i].s;
            pq.push(a[i].f - a[i].s);
        }
        H[i] = sum;
        ans = max(ans, H[i]);
    }


    int rem = n - M - S;
    sum = 0;

    for (int i = n - 1; i >= M; --i) {
        sum += a[i].s;
        if (pqm.size() != rem) {
            sum -= a[i].s;
            pqm.push(a[i].s);
        } else
        if (rem > 0 && pqm.top() > a[i].s)
        {
            sum += pqm.top();
            pqm.pop();
            sum -= a[i].s;
            pqm.push(a[i].s);
        }

        if (pqm.size() == rem)
            ans = max(ans, (i == 0) ? 0 : H[i - 1] + sum);
    }

    cout << ans << endl;
    return 0;

}