package asdf;import java.util.ArrayDeque;
import java.util.Queue;
//1 1 3 1
//2
import java.util.Scanner;public class HorseCount {public static void main(String[] args) {Scanner sc=new Scanner(System.in);String[] size=sc.nextLine().split(" ");int sizex=Integer.parseInt(size[0]);int sizey=Integer.parseInt(size[1]);String[] str=sc.nextLine().split(" ");int x=Integer.parseInt(str[0]);int y=Integer.parseInt(str[1]);int desx=Integer.parseInt(str[2]);int desy=Integer.parseInt(str[3]);horse(x,y,desx,desy,sizex,sizey);sc.close();}private static void horse(int x,int y,int desx,int desy,int sizex,int sizey) {boolean[][] visited=new boolean[9][9];Queue<Node> queue=new ArrayDeque<>();int[][] axes= {{1,2},{1,-2},{2,1},{2,-1},{-1,2},{-1,-2},{-2,1},{-2,-1}};for(int i = 1;i<=8;i++){for(int j = 1;j<=8;j++){visited[i][j] = false; }}Node node=new Node(x,y,0);visited[x][y] = true;    queue.offer(node);while(!queue.isEmpty()) {Node front=queue.poll();int a=front.x;int b=front.y;int step=front.step;        if(a==desx&&b==desy) {System.out.println(step);}else {for(int i=0;i<axes.length;i++) {                    int hx=a+axes[i][0];int hy=b+axes[i][1];int hstep=step+1;Node ho=new Node(hx,hy,hstep);;if(ho.x>=1&&ho.x<=sizex&&ho.y>=1&&ho.y<=sizey&&visited[ho.x][ho.y]==false) {queue.offer(ho);visited[ho.x][ho.y]=true;}}}        }}
}
class Node{ public int x;public int y;public int step;public Node(int x,int y,int step){this.x = x;this.y = y;this.step=step;}
}

//数组大小可以手动设置，怕越界的话可以设置的大一点。boolean[][] visited=new boolean[9][9];比如9可以设置成1000