#include <iostream>
#include <cstring>
#include <vector>
#include <math.h>

using namespace std;

typedef struct{
	int x, y;
}Pos;

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int W,H,Sx,Sy,Ex,Ey;
	cin >> W >> H >> Sx >> Sy >> Ex >> Ey;
	int tmp[H/2][W/2];
	for(int i=0; i<H/2; i++){
		for(int j=0; j<W/2; j++){
			cin >> tmp[i][j];
		}
	}
	vector<string> heights;
	string xd;
	for(int i=0; i<H/2; i++){
		string xd = "";
		for(int j=0; j<W/2; j++){
			xd += tmp[i][j];
			xd += tmp[i][j];
		}
		heights.push_back(xd);
		heights.push_back(xd);
	}
	int dx = Ex - Sx;
	int dy = Ey - Sy;
	double m = double(dy)/dx;
	int D = 2*dy - dx;
	int y = Sy;
	vector<Pos> positions;
	if(Sx > Ex){
		int tmp_S = Sx;
		Sx = Ex;
		Ex = tmp_S;
		tmp_S = Sy;
		Sy = Ey;
		Ey = tmp_S;
	}
	bool flag;
	for(int x=Sx; x<Ex; x+=1){
		Pos tmp;
		if(y == m*x + Sx){
			if(heights[y][x-1] > heights[y][x]){
				flag = true;
			}
			if(m > 0){
				if(flag && heights[y-1][x] <= heights[y][x-1]){
					tmp.x = x-1;
					tmp.y = y;
					positions.push_back(tmp);

				}else if(heights[y-1][x] > heights[x][y]){
					tmp.x = x;
					tmp.y = y-1;
					positions.push_back(tmp);
				}
			}else{
				if(flag && heights[y+1][x] <= heights[y][x-1]){
					tmp.x = x-1;
					tmp.y = y;
					positions.push_back(tmp);
				}else if(heights[y+1][x] > heights[x][y]){
					tmp.x = x;
					tmp.y = y+1;
					positions.push_back(tmp);
				}
			}
		}
	   	tmp.x = x;
		tmp.y = y;
		positions.push_back(tmp);
		if( D < 0 ){
			y = y-1;
			D = D - 2*dx;
		}
		D = D + 2*dy;
	}
	double path_len = sqrt((double(Ex) - Sx)*(double(Ex) - Sx) + (double(Ey) - Sy)*(double(Ey) - Sy));
	int cur_level = heights[positions[0].y][positions[0].x];
	int pos_size = positions.size();
	for(int i=1; i<pos_size; i++){
		int next_height = heights[positions[i].y][positions[i].x]; 
		if(cur_level != next_height){
			path_len += abs(cur_level - next_height);
		}
		cur_level = next_height;
	}
	cout << path_len;
	
	return 0;
}