import collections
N,V,Sx,Sy,Gx,Gy = map(int,input().split())
Sx -= 1
Sy -= 1
Gx -= 1
Gy -= 1
sand = [list(map(int,input().split())) for i in range(N)]
dxy = [(1,0),(-1,0),(0,-1),(0,1)]
lstimes = [[0]*(N) for i in range(N)]
lscost = [[float('INF')]*N for i in range(N)]
lscost[Sy][Sx] = 0
d = collections.deque([(Sy,Sx)])
while d:
    x,y = d.popleft()
    if x == Gy and y == Gx:
        if lscost[x][y] < V:
            print(lstimes[x][y])
            exit()
    for dx,dy in dxy:
        if 0<= x+dx < N and 0 <= y+dy < N:
            if lscost[x+dx][y+dy] > lscost[x][y] + sand[x+dx][y+dy]:
                lscost[x+dx][y+dy] = lscost[x][y] + sand[x+dx][y+dy]
                lstimes[x+dx][y+dy] = lstimes[x][y]+1
                d.append((x+dx,y+dy))
print(-1)