// File coincollecting.cpp created on 02.10.2025 at 11:58:40
#include <bits/stdc++.h>
using i64 = long long;
#ifdef DEBUG
#include "/home/ahmetalp/Desktop/Workplace/debug.h"
#else
#define debug(...) void(23)
#endif
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int N;
std::cin >> N;
std::vector<std::array<int, 2>> A(N * 2);
for (int i = 0; i < N * 2; ++i) {
std::cin >> A[i][0] >> A[i][1];
--A[i][0], --A[i][1];
}
i64 ans = 0;
for (int i = 0; i < N * 2; ++i) {
int x, y;
if (A[i][0] < 0) {
x = 0;
} else if (A[i][0] < N) {
x = A[i][0];
} else {
x = N - 1;
}
if (A[i][1] <= 0) {
y = 0;
} else {
y = 1;
}
ans += std::abs(x - A[i][0]) + std::abs(y - A[i][1]);
A[i][0] = x;
A[i][1] = y;
debug(x, y);
}
{
int cnt[2] {};
for (int i = 0; i < N * 2; ++i) {
cnt[A[i][1]] += 1;
}
ans += std::abs(cnt[0] - cnt[1]) / 2;
}
{
std::vector<int> pre(N + 1);
for (int i = 0; i < N * 2; ++i) {
pre[A[i][0] + 1]++;
}
for (int i = 0; i < N; ++i) {
pre[i + 1] += pre[i];
}
for (int i = 0; i < N; ++i) {
ans += std::abs(2 * (i + 1) - pre[i + 1]);
}
}
std::cout << ans << '\n';
return 0;
}
