import sys
def input(): return sys.stdin.readline().rstrip()
def ii(f=int): return f(input())
def mi(f=int): return map(f, input().split())
def li(f=int): return list(map(f, mi()))

H, W = mi()
A, B = mi()
r1,c1,r2,c2 = mi()
P, Q = mi()

def f(a, b):
    return abs(A - a) + abs(B - b) + abs(P - a) + abs(Q - b) + abs(P - A) + abs(Q - B)

ans = 10**19
for a in range(r1, r2 + 1):
    for b in range(c1, c2 + 1):
        ans = min(ans, f(a,b))
print(ans)