#P3466. Distance to the Prey

Distance to the Prey

Description

Zhizhu is a intelligent spider. His mean of weaving is different from everyone:

His first web was called S0. Then he connected five S0 into a bigger web S1. In the same way he got S2, S3, etc, as the figure above shows. Finally he finished his work S10000!

Today a insect touches the web and gets stuck. The insect is located at (a,b), and Zhizhu is at (c,d). The coordinates are all integers. He wants to know how far he needs to walk in order to reach his prey. Of course, he has to walk along the web S10000.

Input

There are multiple test cases. Each case contains one line consisting of 4 integers a, b, c, d (0 ≤ a,b,c,d ≤ 109).

Output

For each test case you need to print one number, the distance Zhizhu has to walk.

5 3 6 4
2

Hint

The figure above is one part of S10000. Zhi zhu can walk from (6,4) to (6,3), then (5,3).

Source

POJ Monthly--2007.11.25, Yang Yi