Czech ACM Student Chapter
Czech Technical University in Prague
Charles University in Prague
Technical University of Ostrava
acm
ˇ a
Slovak University of Technology
Pavol Jozef Saf´rik University in Koˇice
s
cz
ˇ
University of Zilina
Masaryk University
Matej Bel University in Bansk´ Bystrica
a
University of West Bohemia
CTU Open Contest 2018
Horsemeet
horsemeet.c, horsemeet.cpp, horsemeet.c11, Horsemeet.java, horsemeet.py
Traditional games such as chess or checkers with slight modifications, are also played in Binary
Casino. However, not many people play them, as these games are often referred as boring. The
visitors are more attracted to more dynamic games which cause adrenaline rushes. To attract
players to traditional games, your boss wants to introduce a chess-based game called Horsemeet.
The rules of the game are:
The game is played by two players on a 8 × 8 chessboard. One player plays a white knight and
the other player plays a black knight. The players alternate in moves, the white knight moves
first. In each move a knight is moved from its current position to a random valid position. Valid
position within the chessboard is a position, which is two tiles away in one coordinate and one
tile away in other coordinate from the original position. All moves to a valid position are equally
probable. The first knight to move to a tile already occupied by the other knight wins.
In order to check whether this game could be at least partially interesting to visitors you have
to determine the probability of victory for knights at given start positions. If the probabilities
of victory for both knights differs by less than 10-6 the outcome of such configuration is a draw.
Input Specification
The first line of input contains two integers A and B (1 ≤ A, B ≤ 8), the start position of the
white knight. The second line of each input consists of two integers C and D (1 ≤ C, D ≤ 8),
the start position of the black knight. You can assume both positions are distinct.
Output Specification
Output the knight with a higher probability of victory: "white" or "black". In case of equal
probabilities output "draw".
Sample Input 1
Output for Sample Input 1
11
white
47
Sample Input 2
Output for Sample Input 2
11
black
88
