#!/usr/bin/ python3.8
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
from collections import deque

H, W = map(int, readline().split())
sx, sy = map(int, readline().split())
gx, gy = map(int, readline().split())
sx = H + 1 - sx
gx = H + 1 - gx

print(abs(sx-gx) + abs(sy-gy))