H,W=map(int,input().split())
A,B=map(int,input().split())
R1,C1,R2,C2=map(int,input().split())
P,Q=map(int,input().split())

def d(a,b,c,d):
    return abs(a-c)+abs(b-d)

ans=10**18
for i in range(R1-1,R2):
    for j in range(C1-1,C2):
        ans=min(ans,d(A-1,B-1,i,j)+d(i,j,P-1,Q-1)+d(P-1,Q-1,A-1,B-1))
print(ans)