// >>> TEMPLATES
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;
#define int ll
#define double ld
#define rep(i,n) for (int i = 0; i < (int)(n); i++)
#define rep1(i,n) for (int i = 1; i <= (int)(n); i++)
#define repR(i,n) for (int i = (int)(n)-1; i >= 0; i--)
#define rep1R(i,n) for (int i = (int)(n); i >= 1; i--)
#define loop(i,a,B) for (int i = a; i B; i++)
#define loopR(i,a,B) for (int i = a; i B; i--)
#define all(x) begin(x), end(x)
#define allR(x) rbegin(x), rend(x)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fst first
#define snd second
template <class Int> auto constexpr inf = numeric_limits<Int>::max()/2-1;
auto constexpr INF32 = inf<int32_t>;
auto constexpr INF64 = inf<int64_t>;
auto constexpr INF   = inf<int>;
#ifdef LOCAL
#include "debug.hpp"
#else
#define dump(...) (void)(0)
#define say(x) (void)(0)
#define debug if (0)
#endif
template <class T> using pque_max = priority_queue<T>;
template <class T> using pque_min = priority_queue<T, vector<T>, greater<T> >;
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
ostream& operator<<(ostream& os, T const& v) { bool f = true; for (auto const& x : v) os << (f ? "" : " ") << x, f = false; return os; }
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
istream& operator>>(istream& is, T &v) { for (auto& x : v) is >> x; return is; }
template <class T, class S> ostream& operator<<(ostream& os, pair<T,S> const& p) { return os << "(" << p.first << ", " << p.second << ")"; }
template <class T, class S> istream& operator>>(istream& is, pair<T,S>& p) { return is >> p.first >> p.second; }
struct IOSetup { IOSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } iosetup;
template <class F> struct FixPoint : private F {
    constexpr FixPoint(F&& f) : F(forward<F>(f)) {}
    template <class... T> constexpr auto operator()(T&&... x) const { return F::operator()(*this, forward<T>(x)...); }
};
struct MakeFixPoint {
    template <class F> constexpr auto operator|(F&& f) const { return FixPoint<F>(forward<F>(f)); }
};
#define MFP MakeFixPoint()|
#define def(name, ...) auto name = MFP [&](auto &&name, __VA_ARGS__)
template <class T, size_t d> struct vec_impl {
    using type = vector<typename vec_impl<T,d-1>::type>;
    template <class... U> static type make_v(size_t n, U&&... x) { return type(n, vec_impl<T,d-1>::make_v(forward<U>(x)...)); }
};
template <class T> struct vec_impl<T,0> { using type = T; static type make_v(T const& x = {}) { return x; } };
template <class T, size_t d = 1> using vec = typename vec_impl<T,d>::type;
template <class T, size_t d = 1, class... Args> auto make_v(Args&&... args) { return vec_impl<T,d>::make_v(forward<Args>(args)...); }
template <class T> void quit(T const& x) { cout << x << endl; exit(0); }
template <class T, class U> constexpr bool chmin(T& x, U const& y) { if (x > y) { x = y; return true; } return false; }
template <class T, class U> constexpr bool chmax(T& x, U const& y) { if (x < y) { x = y; return true; } return false; }
template <class It> constexpr auto sumof(It b, It e) {
    using S = typename iterator_traits<It>::value_type;
    using T = conditional_t<is_signed_v<S>,i64,u64>;
    return accumulate(b,e,T{});
}
template <class T> int sz(T const& x) { return x.size(); }
template <class C, class T> int lbd(C const& v, T const& x) {
    return lower_bound(v.begin(), v.end(), x)-v.begin();
}
template <class C, class T> int ubd(C const& v, T const& x) {
    return upper_bound(v.begin(), v.end(), x)-v.begin();
}
const int dx[] = { 1,0,-1,0 };
const int dy[] = { 0,1,0,-1 };
constexpr int popcnt(ll x) { return __builtin_popcountll(x); }
template <class Int> Int rand(Int a, Int b) { // [a,b]
    static mt19937_64 mt{random_device{}()};
    return uniform_int_distribution<Int>(a,b)(mt);
}
i64 irand(i64 a, i64 b) { return rand<i64>(a,b); }
u64 urand(u64 a, u64 b) { return rand<u64>(a,b); }
// <<<
// >>> reord

void reord_impl(vector<int> const&) { }
template <class C, class... Args>
void reord_impl(vector<int> const& idx, C& v, Args&&... args) {
    auto t = v;
    rep (i,v.size()) t[i] = v[idx[i]];
    swap(v,t);
    reord_impl(idx, forward<Args>(args)...);
}
template <class Comp, class C, class... Args,
          class = decltype(declval<Comp>()(0,0))>
void reord(Comp comp, C& v, Args&&... args) {
    vector<int> idx(v.size());
    iota(idx.begin(), idx.end(), 0);
    sort(idx.begin(), idx.end(), comp);
    reord_impl(idx, v, args...);
}
template <class C, class... Args>
void reord(C& v, Args&&... args) {
    vector<int> idx(v.size());
    iota(idx.begin(), idx.end(), 0);
    sort(idx.begin(), idx.end(), [&](int i, int j) { return v[i] < v[j]; });
    reord_impl(idx, v, args...);
}
template <class C, class... Args>
void reordR(C& v, Args&&... args) {
    vector<int> idx(v.size());
    iota(idx.begin(), idx.end(), 0);
    sort(idx.begin(), idx.end(), [&](int i, int j) { return v[i] > v[j]; });
    reord_impl(idx, v, args...);
}

// <<<
// >>> coordinate compression
template <class T>
struct Compress {
    vector<T> v;
    bool ok = false;
    void add(T const& x) { ok = false; v.push_back(x); }
    template <class V>
    void add(V const& u) { ok = false; copy(all(u), back_inserter(v)); }
    template <class... Ts>
    void add(Ts const&... xs) { (int[]){(add(xs),0)...}; }
    void init() { sort(all(v)); v.erase(unique(all(v)), v.end()); ok = true; }
    int size() const { return v.size(); }
    T operator[](int i) const { assert(ok); return v[i]; }
    int find(T const& x) const { assert(ok); auto it = lower_bound(all(v),x); assert(*it == x); return it-v.begin(); }
    void set(T& x) const { x = find(x); }
    template <class V>
    void set(V& u) const { for (auto &x : u) x = find(x); }
    template <class... Ts>
    void set(Ts&... xs) const { (int[]){(set(xs),0)...}; }
};
// <<<
// >>> segment tree
template <class Handler>
struct Segtree : Handler {
    using Value = typename Handler::Value;
    using Handler::unit; // () -> Value
    using Handler::merge; // (Value,Value) -> Value

    vector<Value> v; // use v[1..2*cap-1]
    int cap; // // capacity: power of 2
    int n; // original size

    Segtree() {}
    template <class... T> Segtree(T&&... x) { init(forward<T>(x)...); }

    template <class F, class = decltype(declval<F>()(0))>
    void init(int n, F gen)  {
        assert(n >= 0); this->n = n;
        cap = n; //for (cap = 1; cap < n; cap <<= 1) ;;
        v.resize(2*cap, unit());
        for (int i = 0; i < n; i++) v[cap+i] = gen(i);
        for (int i = cap-1; i >= 1; i--) v[i] = merge(v[2*i],v[2*i+1]);
    }
    void init(int n) { init(n, [&](int) { return unit(); }); }
    void init(int n, Value const& x) { init(n, [&](int) { return x; }); }
    void init(vector<Value> const& v) { init(v.size(), [&](int i) { return v[i]; }); }
    int size() const { return n; }

    void set(int i, Value const& x) {
        assert(0 <= i); assert(i < size());
        i += cap; v[i] = x;
        while (i > 1) i >>= 1, v[i] = merge(v[2*i],v[2*i+1]);
    }
    Value operator[](int i) const { return get(i); }
    Value get(int i) const {
        assert(0 <= i); assert(i < size());
        return v[cap + i];
    }
    // [l,r)
    Value get(int l, int r) const {
        assert(0 <= l); assert(l <= r); assert(r <= size());
        Value x = unit(), y = unit();
        for (l += cap, r += cap; l < r; l >>= 1, r >>= 1) {
            if (l&1) x = merge(x, v[l++]);
            if (r&1) y = merge(v[--r], y);
        }
        return merge(x,y);
    }
    vector<Value> dat() const {
        vector<Value> ret(size());
        for (int i = 0; i < size(); i++) ret[i] = get(i);
        return ret;
    }
};
// <<<

struct RangeMax {
    using Value = int;
    constexpr static Value unit() { return -INF; }
    constexpr static Value merge(Value x, Value y) { return max(x,y); }
};

int32_t main() {
    int n; cin >> n;
    vector<int> x(n),y(n);
    rep (i,n) cin >> x[i] >> y[i];
    reord(x,y);

    Compress<int> Z;
    Z.add(y); Z.init(); Z.set(y);
    dump(Z.v);

    Segtree<RangeMax> seg1(Z.size());
    Segtree<RangeMax> seg2(Z.size());

    int ma = 0;
    rep (i,n) {
        chmax(ma, seg1.get(y[i],Z.size()) + (x[i]-Z[y[i]]));
        seg1.set(y[i], max(seg1[y[i]], -x[i]+Z[y[i]]));

        chmax(ma, seg2.get(0,y[i]) + (x[i]+Z[y[i]]));
        seg2.set(y[i], max(seg2[y[i]], -x[i]-Z[y[i]]));

        dump(seg1.dat());
        dump(seg2.dat());
    }

    cout << ma << endl;

}


Measured memory_bytes: 16260