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Artifact d58d04c710b03f7fddfd1012835304cc836c77a7


#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <functional>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
#include <cassert>
#include <tuple>
using namespace std;
typedef long long LL;
typedef complex<double> CMP;

class TheGridDivOne { public:
	int find(vector <int> x, vector <int> y, int k)
	{
		enum {X, Y};
		typedef tuple<int,int> Point;

		set<Point> blocked;
		map<int, set<int>> x2y;
		x2y[0].emplace(0);
		for(int i=0; i<x.size(); ++i) {
			blocked.emplace(x[i], y[i]);
			x2y[x[i]-1].emplace(y[i]-1);
			x2y[x[i]-1].emplace(y[i]+0);
			x2y[x[i]-1].emplace(y[i]+1);
			x2y[x[i]+0].emplace(y[i]-1);
			x2y[x[i]+0].emplace(y[i]+1);
			x2y[x[i]+1].emplace(y[i]-1);
			x2y[x[i]+1].emplace(y[i]+0);
			x2y[x[i]+1].emplace(y[i]+1);
		}

		map<int, set<int>> x2y_aug = x2y;
		for(auto it=x2y.begin(); it!=x2y.end(); ++it) {
			auto kt = it; ++kt;
			if(kt != x2y.end()) {
				for(int y: it->second)
					x2y_aug[kt->first].emplace(y);
			}
			if(it != x2y.begin()) {
				auto kt = it; --kt;
				for(int y: it->second)
					x2y_aug[kt->first].emplace(y);
			}
		}

		vector<Point> pts;
		for(auto& xys: x2y_aug) {
			int x = xys.first;
			for(int y: xys.second) {
				Point q(x,y);
				if(!blocked.count(q))
					pts.emplace_back(q);
			}
		}

		typedef int Vert;
		const int N = pts.size();
		const int S = std::find(pts.begin(), pts.end(), Point(0,0)) - pts.begin();
		typedef int Cost;
		typedef pair<Cost,Vert> Edge;
		typedef vector<Edge> Edges;
		typedef vector<Edges> Graph;

		Graph G(N);
		for(int i=0; i<N; ++i)
		for(int k=i+1; k<N; ++k) {
			bool connected = true;
			int x1 = get<X>(pts[i]);
			int x2 = get<X>(pts[k]);
			int y1 = get<Y>(pts[i]);
			int y2 = get<Y>(pts[k]);
			for(Point b: blocked) {
				if(min(y1,y2)<=get<Y>(b) && get<Y>(b)<=max(y1,y2) &&
				   min(x1,x2)<=get<X>(b) && get<X>(b)<=max(x1,x2)) {
					connected = false;
					break;
				}
			}
			// If not blocked then add i<-->k with Manhattan cost
			if(connected) {
				G[i].emplace_back(abs(x1-x2)+abs(y1-y2), k);
				G[k].emplace_back(abs(x1-x2)+abs(y1-y2), i);
			}
		}

		// Dijkstra
		priority_queue<Edge, vector<Edge>, greater<Edge>> Q;
		Q.emplace(0, S);
		vector<Cost> D(N, -1);
		while(!Q.empty()) {
			Cost c = Q.top().first;
			Vert v = Q.top().second;
			Q.pop();
			if(D[v]!=-1)
				continue;
			D[v] = c;

			for(auto e: G[v]) {
				Cost c2 = c + e.first;
				Vert q = e.second;
				if(D[q]==-1)
					Q.emplace(c2, q);
			}
		}

		int best = 0;
		for(Vert v=0; v<N; ++v) {
			if(D[v] != -1 && D[v]<=k) {
				// the point
				best = max(best, get<X>(pts[v]));


				// if not blocked...
				Point right(get<X>(pts[v])+1, get<Y>(pts[v]));
				if(blocked.count(right))
					continue;

				// go more east
				bool skip = false;
				for(Edge e: G[v]) {
					Vert u = e.second;
					if(get<Y>(pts[u]) == get<Y>(pts[v]) && get<X>(pts[u]) > get<X>(pts[v])
						&& D[u]!=-1 && D[u]<=k) {
						skip = true;
					}
				}
				if(!skip) {
					int sec = k-D[v];
					best = max(best, get<X>(pts[v]) + sec);
				}
			}
		}

		return best;
	}
};

// BEGIN CUT HERE
#include <ctime>
double start_time; string timer()
 { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
 { os << "{ ";
   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
void verify_case(const int& Expected, const int& Received) {
 bool ok = (Expected == Received);
 if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
 cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
#define END	 verify_case(_, TheGridDivOne().find(x, y, k));}
int main(){

CASE(0)
	int x_[] = {1,1,1,1};
	  vector <int> x(x_, x_+sizeof(x_)/sizeof(*x_)); 
	int y_[] = {-2,-1,0,1};
	  vector <int> y(y_, y_+sizeof(y_)/sizeof(*y_)); 
	int k = 4; 
	int _ = 2; 
END
CASE(1)
	int x_[] = {-1, 0, 0, 1};
	  vector <int> x(x_, x_+sizeof(x_)/sizeof(*x_)); 
	int y_[] = {0, -1, 1, 0};
	  vector <int> y(y_, y_+sizeof(y_)/sizeof(*y_)); 
	int k = 9; 
	int _ = 0; 
END
CASE(2)
	vector <int> x; 
	vector <int> y; 
	int k = 1000; 
	int _ = 1000; 
END
CASE(3)
	int x_[] = {1,0,0,-1,-1,-2,-2,-3,-3,-4,-4};
	  vector <int> x(x_, x_+sizeof(x_)/sizeof(*x_)); 
	int y_[] = {0,-1,1,-2,2,-3,3,-4,4,-5,5};
	  vector <int> y(y_, y_+sizeof(y_)/sizeof(*y_)); 
	int k = 47; 
	int _ = 31; 
END
/*
CASE(4)
	int x_[] = ;
	  vector <int> x(x_, x_+sizeof(x_)/sizeof(*x_)); 
	int y_[] = ;
	  vector <int> y(y_, y_+sizeof(y_)/sizeof(*y_)); 
	int k = ; 
	int _ = ; 
END
CASE(5)
	int x_[] = ;
	  vector <int> x(x_, x_+sizeof(x_)/sizeof(*x_)); 
	int y_[] = ;
	  vector <int> y(y_, y_+sizeof(y_)/sizeof(*y_)); 
	int k = ; 
	int _ = ; 
END
*/
}
// END CUT HERE