import java.util.*;
import java.io.*;

public class Main {
	public static void main (String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] first = br.readLine().split(" ", 6);
		int n = Integer.parseInt(first[0]);
		int v = Integer.parseInt(first[1]);
		int sc = Integer.parseInt(first[2]) - 1;
		int sr = Integer.parseInt(first[3]) - 1;
		int gc = Integer.parseInt(first[4]) - 1;
		int gr = Integer.parseInt(first[5]) - 1;
		int[][] field = new int[n][n];
		int[][] costs = new int[n][n];
		for (int i = 0; i < n; i++) {
		    String[] line = br.readLine().split(" ", n);
		    for (int j = 0; j < n; j++) {
		        field[i][j] = line[j].charAt(0) - '0';
		    }
		    Arrays.fill(costs[i], Integer.MAX_VALUE);
		}
		PriorityQueue<Path> queue = new PriorityQueue<>();
		queue.add(new Path(sr, sc, -field[sr][sc], 0));
		while (queue.size() > 0) {
		    Path p = queue.poll();
		    if (p.row < 0 || p.row >= n || p.col < 0 || p.col >= n) {
		        continue;
		    }
		    p.value += field[p.row][p.col];
		    if (p.value >= v || costs[p.row][p.col] <= p.count) {
		        continue;
		    }
		    costs[p.row][p.col] = p.count;
		    queue.add(new Path(p.row + 1, p.col, p.value, p.count + 1));
		    queue.add(new Path(p.row - 1, p.col, p.value, p.count + 1));
		    queue.add(new Path(p.row, p.col + 1, p.value, p.count + 1));
		    queue.add(new Path(p.row, p.col - 1, p.value, p.count + 1));
		}
		if (costs[gr][gc] == Integer.MAX_VALUE) {
		    System.out.println(-1);
		} else {
		    System.out.println(costs[gr][gc]);
		}
	}
	
	static class Path implements Comparable<Path> {
	    int row;
	    int col;
	    int value;
	    int count;
	    
	    public Path(int row, int col, int value, int count) {
	        this.row = row;
	        this.col = col;
	        this.value = value;
	        this.count = count;
	    }
	    
	    public int compareTo(Path another) {
	        return value - another.value;
	    }
	}
}