#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
typedef long long ll;
typedef pair<ll, ll> ii;
const int maxn = 1e5 + 7;
ll n, r[maxn], s[maxn];
ii lift(ll x, ll y, ll k){
if (k <= 0) return {x, y};
if (x == 0) return {0, y - k};
if (y == 0) return {x - k, 0};
if ((x & -x) < (y & -y))
return lift(x - min(k, x & -x), y, k - (x & -x));
else
return lift(x, y - min(k, y & -y), k - (y & -y));
}
ii lca(ll x1, ll y1, ll x2, ll y2){
if ((x1 + y1) > (x2 + y2)){
swap(x1, x2);
swap(y1, y2);
}
ii lf = lift(x2, y2, x2 + y2 - x1 - y1);
x2 = lf.ff, y2 = lf.ss;
ll db = x1 + y1;
ll l = 0, r = db;
while(l < r){
ll m = (l + r) / 2;
ii la = lift(x1, y1, m);
ii lb = lift(x2, y2, m);
if (la == lb) r = m;
else l = m + 1;
}
return lift(x1, y1, l);
}
ll subtree(ll x, ll y){
ll ret = 0;
for (int i = 1; i <= n; i++){
if (x + y > r[i] + s[i]) continue;
ii lf = lift(r[i], s[i], r[i] + s[i] - x - y);
if (lf == make_pair(x, y)) ret++;
}
return ret;
}
bool check(ll x, ll y){
ll ch1 = subtree(x + 1, y), ch2 = subtree(x, y + 1);
if (ch1 * 2 > n || ch2 * 2 > n)
return 0;
return 1;
}
int main(){
srand(time(0));
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n;
for (int i = 1; i <= n; i++)
cin >> r[i] >> s[i];
ll ansr, anss;
while(true){
int i = (rand() * rand()) % n + 1;
ll le = 0, ri = r[i] + s[i];
while(le < ri){
ll m = (le + ri) / 2;
ii lf = lift(r[i], s[i], m);
ll st = subtree(lf.ff, lf.ss);
if (2 * st >= n) ri = m;
else le = m + 1;
}
ii lf = lift(r[i], s[i], le);
ll x = lf.ff, y = lf.ss;
if (check(x, y)){
ansr = x, anss = y;
break;
}
}
ll ans = 0;
for (int i = 1; i <= n; i++){
ii lc = lca(r[i], s[i], ansr, anss);
ll x = lc.ff, y = lc.ss;
ans += r[i];
ans += s[i];
ans += ansr;
ans += anss;
ans -= x;
ans -= x;
ans -= y;
ans -= y;
}
cout << ans << "\n";
return 0;
}
