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())

i = min(max(A, R1), R2)   
j = min(max(B, C1), C2)   

print(abs(A-i) + abs(B-j) + abs(i-P) + abs(j-Q) + abs(P-A) + abs(Q-B))