#include <iostream>
#include<stdio.h>
#include <cmath>
#include<algorithm>
#include <set>
#include <cassert>
#include <numeric>
#include <fstream>
#define endl '\n'
#define int long long
typedef long long ll;
using namespace std;
struct slope_trick
{
const ll inf = 9223372036854775807ll;
std::multiset < ll > left_set, right_set;
ll height;
slope_trick()
{
height = 0;
}
ll get_right()
{
if (right_set.empty())
return inf;
return *right_set.begin();
}
ll get_left()
{
if (left_set.empty())
return -inf;
return *left_set.rbegin();
}
void add_basic(ll v) /// adds |x - v|
{
ll left = get_left(), right = get_right();
if (v >= left && v <= right)
{
left_set.insert(v);
right_set.insert(v);
}
else if (v < left)
{
left_set.insert(v);
left_set.insert(v);
right_set.insert(left);
left_set.erase(left_set.find(left));
height = height + abs(v - left);
}
}
void print_slope_trick()
{
std::cout << "left_slope" << endl;
for (int cor : left_set)
std::cout << cor << " ";
std::cout << endl;
std::cout << "right_slope" << endl;
for (int cor : right_set)
std::cout << cor << " ";
std::cout << endl;
std::cout << "height " << height << endl;
}
void prefix_minimum()
{
right_set.clear();
///right_set.clear();
}
ll query_vlaue(ll debit)
{
ll last = get_left(), slope = 0, base = height;
while(left_set.size() > 0 && get_left() > debit)
{
ll distance = last - get_left();
base = base + distance * slope;
slope ++;
last = last - distance;
assert(left_set.size() > 0);
left_set.erase(prev(left_set.end()));
}
if (slope != 0)
{
assert(last >= debit);
base = base + (last - debit) * slope;
}
return base;
}
};
const int maxn = 5000010;
int n;
ll a[maxn], b[maxn];
ll x[maxn], pref[maxn];
void solve()
{
std::cin >> n;
for (int i = 1; i <= n; i ++)
{
std::cin >> a[i] >> b[i];
x[i] = a[i] - b[i];
pref[i] = pref[i - 1] + x[i];
}
ll sum = 0;
for (int i = 1; i <= n; i ++)
{
sum += abs(pref[i]);
}
slope_trick st;
ll cnt = 0;
for (int i = 1; i <= n; i ++)
{
if (pref[i] < 0)
{
st.height += -pref[i];
cnt ++;
st.add_basic(0);
}
else
st.add_basic(pref[i]), cnt ++;
st.prefix_minimum();
//std::cout << "--------------------" << endl;
// st.print_slope_trick();
}
///std::cout << "dasdas" << endl;
ll sumf = 0;
for (ll val : st.left_set)
sumf += val;
sumf += st.height;
ll ans = st.query_vlaue(pref[n]);
///std::cout << "-----------------" << endl;
std::cout << ans << endl;
}
void speed()
{
std::ios_base::sync_with_stdio(false);
std::cin.tie(NULL);
std::cout.tie(NULL);
}
signed main()
{
///speed();
///freopen("test.txt","r", stdin);
solve();
return 0;
}
