#include<bits/stdc++.h>
#define ll long long
#define pll pair<ll, ll>
#define fi first
#define se second
using namespace std;
int n, m, s;
const int maxn = 1e6 + 3;
const int inf = 1e9;
pll p[maxn + 3];
priority_queue<int, vector<int>, greater<int>>pq1, pq2;
ll l[maxn + 3], r[maxn + 3], ans;
bool cmp(pll a, pll b)
{
return a.fi - a.se < b.fi - b.se;
}
int main()
{
// freopen("SCHOOL.INP", "r", stdin);
// freopen("SCHOOL.OUT", "w", stdout);
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> m >> s;
for(int i = 1; i <= n; i++)
{
cin >> p[i].fi >> p[i].se;
}
sort(p + 1, p + n + 1, cmp);
/*for(int i = 1; i <= n; i++)
{
cout << p[i].first << ' ' << p[i].second << '\n';
} cout << '\n';*/
for(int i = 1; i <= s; i++)
{
pq1.push(p[i].se);
ans += p[i].se;
l[i] = ans;
}
for(int i = s + 1; i <= n; i++)
{
if(p[i].se > pq1.top() && !pq1.empty())
{
ans = ans + p[i].se - pq1.top();
}
l[i] = ans;
}
ll ans = 0;
for(int i = n; i >= n - m + 1; i--)
{
pq2.push(p[i].fi);
ans += p[i].fi;
r[i] = ans;
}
//cout << ans;
for(int i = n - m; i >= 1; i--)
{
if(p[i].fi > pq2.top() && !pq2.empty())
{
ans = ans + p[i].fi - pq2.top();
}
r[i] = ans;
}
ans = -inf;
for(int i = 1; i < n; i++)
{
ans = max(ans, l[i] + r[i + 1]);
}
cout << ans;
}
