#include <iostream>
#include <cstdio>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <cstring>
#include <string>
#include <cmath>
using namespace std;

string problem = "school";

const int MAXN = 300000;
int n, m, s;
pair<int,int> p[MAXN];

void solve(){
    scanf("%d%d%d",&n,&m,&s);
    for (int i=0; i<n; ++i) scanf("%d%d",&p[i].first,&p[i].second);
    sort(p, p+n);
    priority_queue<pair<int,pair<int,int> > > q;
    long long sa=0, sb=0, st=0;
    for (int i=n-m; i<n; ++i) {
        q.push(make_pair(-(p[i].first-p[i].second),p[i]));
        sa += p[i].first;
    }
    multiset<int> h;
    vector<int> bs;
    for (int i=0; i<n-m; ++i) bs.push_back(p[i].second);
    sort(bs.begin(), bs.end());
    for (int i=0; i<s; ++i) {
        h.insert(bs[bs.size()-i-1]);
        st += bs[bs.size()-i-1];
    }

    long long res = sa+st;
    for (int i=n-m-1; i>=n-m-s; --i){
        if (!h.empty() && *h.begin()<p[i].second){
            st -= p[i].second;
            h.erase(h.find(p[i].second));
        } else {
            st -= *h.begin();
            h.erase(h.begin());
        }
        if (-q.top().first >= p[i].first-p[i].second){
            sb += p[i].second;
        } else {
            sa -= q.top().second.first;
            sb += q.top().second.second;
            q.pop();
            sa += p[i].first;
            q.push(make_pair(-(p[i].first-p[i].second),p[i]));
        }
        if (sa+sb+st > res){
            res=sa+sb+st;
        }
    }

    cout << res << endl;
}


int main(){

#ifdef KP_HOME
    freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
#else
    freopen((problem+".in").c_str(),"r",stdin);
    freopen((problem+".out").c_str(),"w",stdout);
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
#endif

    solve();

    return 0;
}