HZNUOJ

Flipping colors

Tags:
Time Limit:  1 s      Memory Limit:   128 MB
Submission:5     AC:1     Score:99.89

Description

A rectangle with sides parallel to the x-y axes and its left-lower corner at (0, 0) is being painted. The rectangle may be thought of as a flat-screen display with almost infinite resolution; initially the entire rectangle is black. Two numbers are given 0 < h, v < 1 and then

Given a point in the original rectangle but not on the boundary of any rectangle that turns up in the process of painting, determine the color of the point.

Input contains multiple cases. The first line of each case contains 4 numbers, the length of the rectangle H, the height of the rectangle V and then the numbers h and v. The next line contains one integer number n, the number of points to consider. The following n lines contain two numbers each, the x and the y coordinate of a point.

Organize your output as shown in the sample. For each point from input print the color of the point.

Samples

input
81 32 0.333333333333 0.5 6 16 30 16 25 16 12.0001 16 11.9999 16 7.987654321 16 7.0123456789 10 10 0.123456789 0.987654321 2 0.432 0.9876 9.432 0.9876 0 0 0 0
output
Case 1: black black white black white white Case 2: white black