#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for (auto i=(a); i<(b); ++i)
#define iter(it,c) for (auto it = (c).begin(); it != (c).end(); ++it)
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;
typedef long long ll;
const int INF = 2147483647;

int main() {
    int n;
    cin >> n;

    int mna = INF,
        mxa = -INF,
        mnb = INF,
        mxb = -INF;

    rep(i,0,n) {
        int x, y;
        cin >> x >> y;

        mna = min(mna, x+y);
        mxa = max(mxa, x+y);

        mnb = min(mnb, x-y);
        mxb = max(mxb, x-y);
    }

    int res = ((mxa-mna+1)+(mxb-mnb+1))+2;

    if ((mna == mxa) ^ (mnb == mxb)) {
        res++;
    }
    cout << res << endl;

    return 0;
}