#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
using namespace std;
using namespace __gnu_pbds;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define s second
#define int long long
#define pii pair<int,int>
#define ar array
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
tree_order_statistics_node_update> ordered_set;
const int inf = 1e17 + 7;
const int mod = 1e9 + 7;
const int N = 3e5 + 5;
const int md = 998244353;
int binpow(int a, int b){
if(b == 0)return 1;
if(b % 2 == 0){
int c = binpow(a,b/2);
return (c*c)%mod;
}
return (binpow(a,b-1)*a)%mod;
}
int divi(int a, int b){
return (a*(binpow(b,mod-2)))%mod;
}
int n,m,k;
int dp[N][2];
void solve(){
cin >> n >> m >> k;
vector<pair<int,pii>>v(n);
for(int i = 0;i<n;i++){
int a,b;
cin >> a >> b;
v[i] = {a-b,{a,b}};
}
sort(rall(v));
int sum = 0;
multiset <int> st;
for(int i = 0;i<n;i++){
st.insert(v[i].s.f);
sum += v[i].s.f;
if(st.size() > m){
sum -= *st.begin();
st.erase(st.begin());
}
dp[i+1][0] = sum;
}
sum = 0;
st.clear();
for(int i = n-1;i>=0;i--){
st.insert(v[i].s.s);
sum += v[i].s.s;
if(st.size() > k){
sum -= *st.begin();
st.erase(st.begin());
}
dp[i+1][1] = sum;
}
int ans = 0;
for(int i = m;i<= n - k;i++){
umax(ans, dp[i][0] + dp[i+1][1]);
}
cout << ans << "\n";
}
/*
2
2
2 1
4
2 3 1 4
*/
signed main()
{
// freopen("seq.in", "r", stdin);
// freopen("seq.out", "w", stdout);
ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
int tt=1;//cin>>tt;
while(tt--)solve();
}
