from collections import deque
from sys import exit

N, V, Sx, Sy, Gx, Gy = map(int, input().split())
Sx, Sy, Gx, Gy = map(lambda x: x - 1, (Sx, Sy, Gx, Gy))
L = [tuple(map(int, input().split())) for _ in range(N)]
cost_table = [[V] * N for _ in range(N)]
cost_table[Sy][Sx] = 0

d = deque([(Sy, Sx, 0)])
while d:
    y, x, t = d.popleft()
    for dy, dx in ((1, 0), (-1, 0), (0, 1), (0, -1)):
        if 0 <= y + dy < N and 0 <= x + dx < N and cost_table[y + dy][x + dx] > cost_table[y][x] + L[y + dy][x + dx]:
            d.append((y + dy, x + dx, t + 1))
            cost_table[y + dy][x + dx] = cost_table[y][x] + L[y + dy][x + dx]
            if (x + dx, y + dy) == (Gx, Gy):
                print(t + 1)
                exit()
print(-1)