#include "bits/stdc++.h"
using namespace std;
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()
#define int long long
const int mxn = 2e5+5;
int N,X[mxn],Y[mxn];
int A[mxn];
signed main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin>>N;
int res = 0;
for (int i=0; i<2*N; i++) {
cin>>X[i]>>Y[i];
if (X[i] < 1) {
res += 1-X[i];
X[i] = 1;
}
if (X[i] > N) {
res += X[i]-N;
X[i] = N;
}
if (Y[i] < 1) {
res += 1-Y[i];
Y[i] = 1;
}
if (Y[i] > 2) {
res += Y[i]-2;
Y[i] = 2;
}
}
int c1 = 0, c2 = 0;
for (int i=0; i<2*N; i++) {
if (Y[i] == 1) c1++;
else c2++;
}
res += max(c1,c2)-N;
for (int i=0; i<2*N; i++) {
A[X[i]]++;
}
for (int i=1; i<=N; i++) {
A[i] += A[i-1];
res += abs(A[i]-2*i);
}
cout<<res;
return 0;
}
