import java.io.*;
import java.util.*;
import java.util.function.*;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int k = sc.nextInt();
        Point[] points = new Point[n + 2];
        for (int i = 0; i < n + 2; i++) {
            points[i] = new Point(sc.nextInt(), sc.nextInt());
        }
        int[][] distances = new int[n + 2][n + 2];
        for (int i = 0; i < n + 2; i++) {
            for (int j = i + 1; j < n + 2; j++) {
                distances[i][j] = points[i].getDistance(points[j]);
                distances[j][i] = distances[i][j];
            }
        }
        int left = 0;
        int right = 200000;
        PriorityQueue<Path> queue = new PriorityQueue<>();
        int[] costs = new int[n + 2];
        while (right - left > 1) {
            int m = (left + right) / 2;
            Arrays.fill(costs, Integer.MAX_VALUE);
            queue.add(new Path(0, 0));
            while (queue.size() > 0) {
                Path p = queue.poll();
                if (costs[p.idx] <= p.value) {
                    continue;
                }
                costs[p.idx] = p.value;
                for (int i = 0; i < n + 2; i++) {
                    if (costs[i] < Integer.MAX_VALUE) {
                        continue;
                    }
                    queue.add(new Path(i, p.value + (distances[p.idx][i] - 1) / m));
                }
            }
            if (costs[1] <= k) {
                right = m;
            } else {
                left = m;
            }
        }
        System.out.println(right);
    }
    
    static class Path implements Comparable<Path> {
        int idx;
        int value;
        
        public Path (int idx, int value) {
            this.idx = idx;
            this.value = value;
        }
        
        public int compareTo(Path another) {
            return value - another.value;
        }
    }
    
    static class Point {
        int x;
        int y;
        
        public Point(int x, int y) {
            this.x = x;
            this.y = y;
        }
        
        public int getDistance(Point p) {
            return Math.abs(x - p.x) + Math.abs(y - p.y);
        }
    }
}
class Scanner {
    BufferedReader br;
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() {
        try {
            br = new BufferedReader(new InputStreamReader(System.in));
        } catch (Exception e) {
            
        }
    }
    
    public int nextInt() {
        return Integer.parseInt(next());
    }
    
    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public double nextDouble() {
        return Double.parseDouble(next());
    }
    
    public String next() {
        try {
            while (!st.hasMoreTokens()) {
                st = new StringTokenizer(br.readLine());
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            return st.nextToken();
        }
    }
    
}