#include <iostream>
#include <queue>

int N, M;
int sx, sy, fx, fy;

int grid[110][110];

struct coor{
    int x,y;
};

//Generic Class
queue<struct coor> q;

int main() {

        scanf("%d %d", &N, &M);
        scanf("%d %d", &sx, &sy);
        scanf("%d %d", &fx. &fy);

        q.push({sx, sy});


        //-----solution------------------------------------
    

        while(q.size() > 0) {
            auto c = q.front(); //peek //auto -> 자동으로 변수 지정)
            q.pop();

            if(c.x == fx && c.y == fy){
                //destination
                printf("%d\n", grid[c.x][c.y]);
            }

            int dx[] ={1,1,-1,-1,2,2,-2,-2};
            int dy[] ={2,-2,2,-2,1,-1,1,-1};
            
            for(int i =0; i <8; i++) {
                int nx = c.x + dx[i];
                int ny = c.y + dy]i];


                if(!(1 < nx && nx <=N && 1<= ny && ny <= M))
                    continue;

                if(grid[nx][ny]) !=0)
                    continue;
                
                grid[nx][ny] = grid[c.x][c.y]+1
                q.push({nx, ny});
            }
        }

    







    return 0;
}