from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
input = sys.stdin.readline

N,V,sy,sx,gy,gx = map(int,input().split())
sx -= 1
sy -= 1
gx -= 1
gy -= 1
A = [list(map(int,input().split())) for _ in range(N)]
e = [[] for _ in range(N**4)]
INF = (1<<60)
def dijkstra(s,e):
    
    N = len(e)
    dist = [INF]*N
    dist[s]=0
    h = []
    heappush(h,(0,s))
    while h:
        nw,v = heappop(h)
        if dist[v]!=nw:
            continue
        for iv,ic in e[v]:
            nc = ic + nw
            if nc < dist[iv]:
                dist[iv] = nc
                heappush(h,(nc,iv))
    return dist
    
H = N
W = N
def nb(x,y):
    tmp = []
    if x+1<H:
        tmp.append((x+1,y))
    if x-1>=0:
        tmp.append((x-1,y))
    if y+1<W:
        tmp.append((x,y+1))
    if y-1>=0:
        tmp.append((x,y-1))
    return tmp

M = N**2
for i in range(H):
    for j in range(W):
        s = N*i + j
        for ix,iy in nb(i,j):
            t = N*ix + iy
            a = A[ix][iy]
            for n in range(M-1):
                ss = n*M + s
                tt = (n+1)*M + t
                e[ss].append((tt,a))
                
                
d = dijkstra(sx*N+sy,e)    
g = N*gx + gy
ans = INF
for i in range(M):
    gg = i*M + g
    if d[gg]<V:
        print(i)
        exit()
print(-1)