import java.util.*;

class Main {
    static double distance;
    static int[][] heights;
    static int currentHeight;
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        int w = in.nextInt();
        int h = in.nextInt();
        int sx = in.nextInt();
        int sy = in.nextInt();
        int ex = in.nextInt();
        int ey = in.nextInt();

        heights = new int[w/2][h/2];

        for (int y = 0; y < h/2; y++) {
            for (int x = 0; x < w/2; x++) {
                int input = in.nextInt();
                heights[x][y] = input;
            }
        }

        currentHeight = heights[sx/2][sy/2];

        distance = Math.sqrt((ey - sy) * (ey - sy) + (ex - sx) * (ex - sx));
        raytrace(sx/2, sy/2, ex/2, ey/2);
        System.out.println(distance);
    }

    static void visit(int x, int y) {
        distance += Math.abs(heights[x][y] - currentHeight);
        currentHeight = heights[x][y];
    }

    static void point(int x1, int y1, int x2, int y2) {
        int height = Math.min(heights[x1][y1], heights[x2][y2]);
        if (currentHeight < height) {
            distance += Math.abs(height - currentHeight);
            currentHeight = height;
        }
    }


    //source: http://playtechs.blogspot.com/2007/03/raytracing-on-grid.html, edited
    static void raytrace(int x0, int y0, int x1, int y1)
    {
        int dx = Math.abs(x1 - x0);
        int dy = Math.abs(y1 - y0);
        int x = x0;
        int y = y0;
        int n = 1 + dx + dy;
        int x_inc = (x1 > x0) ? 1 : -1;
        int y_inc = (y1 > y0) ? 1 : -1;
        int error = dx - dy;
        dx *= 2;
        dy *= 2;

        for (; n > 0; --n)
        {
            visit(x, y);

            if (error == 0) {
                n--;
                if (n == 0)
                    break;
                point(x + x_inc, y, x, y + y_inc);
                x += x_inc;
                y += y_inc;
                error -= dy;
                error += dx;
                continue;
            }
            if (error > 0)
            {
                x += x_inc;
                error -= dy;
            }
            else
            {
                y += y_inc;
                error += dx;
            }
        }
    }
}