#include <iostream>
#include <set>
#include <vector>
#include <cmath>
#include <cassert>
using namespace std;
typedef long long LL;
class Wall{
public:
LL start, end;
bool hori;
LL pos;
bool is_null;
int id;
};
vector<Wall> walls;
Wall go_left(LL x1, LL y1){
Wall best; best.is_null = true;
for(auto wall : walls){
if(!wall.hori && wall.pos < x1){
if(y1 >= wall.start && y1 <= wall.end){
if(best.is_null || wall.pos > best.pos)
best = wall;
}
}
}
return best;
}
Wall go_right(LL x1, LL y1){
Wall best; best.is_null = true;
for(auto wall : walls){
if(!wall.hori && wall.pos > x1){
if(y1 >= wall.start && y1 <= wall.end){
if(best.is_null || wall.pos < best.pos)
best = wall;
}
}
}
return best;
}
Wall go_up(LL x1, LL y1){
Wall best; best.is_null = true;
for(auto wall : walls){
if(wall.hori && wall.pos > y1){
if(x1 >= wall.start && x1 <= wall.end){
if(best.is_null || wall.pos < best.pos)
best = wall;
}
}
}
return best;
}
Wall go_down(LL x1, LL y1){
Wall best; best.is_null = true;
for(auto wall : walls){
if(wall.hori && wall.pos < y1){
if(x1 >= wall.start && x1 <= wall.end){
if(best.is_null || wall.pos > best.pos)
best = wall;
}
}
}
return best;
}
bool can_see(LL x1, LL y1, LL x2, LL y2){
if(go_left(x1,y1).id == go_left(x2,y2).id && go_right(x1,y1).id == go_right(x2,y2).id) return true;
if(go_up(x1,y1).id == go_up(x2,y2).id && go_down(x1,y1).id == go_down(x2,y2).id) return true;
return false;
}
LL manhattan(LL x1, LL y1, LL x2, LL y2){
return abs(x1-x2) + abs(y1-y2);
}
int main(){
cin.tie(0);
ios_base::sync_with_stdio(0);
LL y1,x1,y2,x2;
cin >> y1 >> x1 >> y2 >> x2;
y1 = -y1; y2 = -y2;
LL px = 0; LL py = 0;
LL step = 1;
vector<pair<LL,LL> > corners;
vector<LL> corner_distances;
corners.push_back({-1,1});
corners.push_back({-1,-1});
corner_distances.push_back(0);
corner_distances.push_back(2);
for(int i = 0; i < 1000; i++){
Wall W;
// Right
step *= 2;
W.start = px; px += step; W.end = px;
W.pos = py;
W.hori = true;
W.is_null = false;
W.id = step;
walls.push_back(W);
corners.push_back({corners.back().first + step + 2, corners.back().second});
corner_distances.push_back(step + 2);
// Up
step *= 2;
W.start = py; py += step; W.end = py;
W.pos = px;
W.hori = false;
W.is_null = false;
W.id = step;
walls.push_back(W);
corners.push_back({corners.back().first, corners.back().second + step + 2});
corner_distances.push_back(step + 2);
// Left
step *= 2;
W.end = px; px -= step; W.start = px;
W.pos = py;
W.hori = true;
W.is_null = false;
W.id = step;
walls.push_back(W);
corners.push_back({corners.back().first - step - 2, corners.back().second});
corner_distances.push_back(step + 2);
// Down
step *= 2;
W.end = py; py -= step; W.start = py;
W.pos = px;
W.hori = false;
W.is_null = false;
W.id = step;
walls.push_back(W);
corners.push_back({corners.back().first, corners.back().second - step - 2});
corner_distances.push_back(step + 2);
if(step >= 1e17) break;
}
/*
for(auto W : walls) cout << W.start << " " << W.end << " " << W.pos << endl;
for(auto p : corners) cout << p.first << " " << p.second << endl;
if(can_see(x1,y1,x2,y2)){
cout << abs(x1-x2) + abs(y1-y2) << endl;
}*/
vector<LL> visible_A, visible_B;
for(int i = 0; i < corners.size(); i++){
auto p = corners[i];
if(can_see(x1,y1,p.first,p.second))
visible_A.push_back(i);
if(can_see(x2,y2,p.first,p.second))
visible_B.push_back(i);
}
LL ans = 1e18;
for(auto c1 : visible_A){
for(auto c2 : visible_B){
LL d = 0;
for(int i = c1 + 1; i <= c2; i++){
//cout << "+" << corner_distances[i] << endl;
d += corner_distances[i];
}
//cout << c1 << " " << c2 << " " << d << endl;
ans = min(ans,d + manhattan(x1,y1,corners[c1].first, corners[c1].second)
+ manhattan(x2,y2,corners[c2].first, corners[c2].second)
);
}
}
cout << ans << endl;
/*
cout << "visible A (" << x1 << " " << y1 << ")" << endl;
for(auto p : visible_A) cout << p.first << " " << p.second << endl;
cout << "visible B (" << x2 << " " << y2 << ")" << endl;
for(auto p : visible_B) cout << p.first << " " << p.second << endl;
*/
/*
cout << go_left(3,-1).id << " " << go_right(3,-1).id << endl;
cout << go_up(3,-1).id << " " << go_down(3,-1).id << endl;
cout << go_left(-8,3).id << " " << go_right(-8,3).id << endl;
cout << go_up(-8,3).id << " " << go_down(-8,3).id << endl;
*/
/*for(int i = -5; i < 6; i++){
cout << i << " " << can_see(-3,2,i,-1) << endl;
}*/
/*
for(int i = -15; i <= 15; i++){
cout << i << " " << go_up(i,-1).id << endl;
}*/
}
