import java.io.*;
import java.util.*;
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[][] matrix = new int[n + 2][n + 2];
        for (int i = 0; i < n + 2; i++) {
            for (int j = i + 1; j < n + 2; j++) {
                int d = points[i].getDixtance(points[j]);
                matrix[i][j] = d;
                matrix[j][i] = d;
            }
        }
        PriorityQueue<Path> queue = new PriorityQueue<>();
        int[] costs = new int[n + 2];
        int left = 0;
        int right = Integer.MAX_VALUE / 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) {
                        queue.add(new Path(i, p.value + (matrix[i][p.idx] - 1) / m));
                    }
                }
            }
            if (costs[1] > k) {
                left = m;
            } else {
                right = m;
            }
        }
        System.out.println(right);
    }
    
    static class Point {
        int x;
        int y;
        
        public Point(int x, int y) {
            this.x = x;
            this.y = y;
        }
        
        public int getDixtance(Point p) {
            return Math.abs(x - p.x) + Math.abs(y - p.y);
        }
    }
    
    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;
        }
    }
}
class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}