Problem B. Box of quarters

Author:A. Klenin, I. Blinov   Time limit:3 sec
Input file:Standard input   Memory limit:256 Mb
Output file:Standard output  


Given a rectangle specified by the coordinates of the lower left corner (x1, y1) and the upper right corner (x2, y2), your program must determine how many quarters of the coordinate system it intersects with.

A rectangle intersects with the coordinate quarter if at least one of its points lies in it. If the point of the rectangle lies on the OX axis or the OY axis, it is considered that it does not belong to any coordinate quarter.

Input format

Input contains four integers x1, y1, x2, y2.

Output format

Output must contain a single integer — the number of coordinate quarters intersecting the rectangle.


100 ≤ x1 < x2 ≤ 100

100 ≤ y1 < y2 ≤ 100

Sample tests

No. Standard input Standard output
-3 -3 3 3
0 0 100 100

0.110s 0.016s 15