#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define pb push_back
const int mod=998244353, maxn=3e5+5;
int n, m, s;
pair<int, int> a[maxn];
priority_queue<int, vector<int>, greater<int>> pq;
ll val, pf[maxn], sf[maxn], ans;
int main() {
ios_base::sync_with_stdio(false); cin.tie(NULL);
cin >> n >> m >> s;
for(int i=1; i<=n; i++) cin >> a[i].fi >> a[i].se;
sort(a+1, a+n+1, [](auto ki, auto ka) {
return ki.fi-ki.se>ka.fi-ka.se;
});
for(int i=1; i<=m; i++) {
pq.push(a[i].fi);
val+=a[i].fi;
if(i==m) pf[i]=val;
}
for(int i=m+1; i<=n; i++) {
if(a[i].fi>pq.top()) {
val+=a[i].fi-pq.top();
pq.pop();
pq.push(a[i].fi);
}
pf[i]=val;
}
val=0;
while(!pq.empty()) pq.pop();
for(int i=n; i>=n-s+1; i--) {
pq.push(a[i].se);
val+=a[i].se;
if(i==n-s+1) sf[i]=val;
}
for(int i=n-s; i>0; i--) {
if(a[i].se>pq.top()) {
val+=a[i].se-pq.top();
pq.pop();
pq.push(a[i].fi);
}
sf[i]=val;
}
for(int i=m; i<=n-s; i++) ans=max(ans, pf[i]+sf[i+1]);
cout << ans << '\n';
}
