A basic input creation script and some random inputs generated by it.

create_input.rb

#!/usr/bin/env ruby
# 
# This script creates checkerboard inputs for CS325 Program #4.
#
# Carlos Agarie
#

prng = Random.new

# Arbitrarily decided that 80% are checkers and 20% are kings.
red_checkers = %w{RC RC RC RC RK}
black_checkers = %w{BC BC BC BC BK}
p = red_checkers.size

# P(red checker) = P(black checker) = 12/64 = 3/16
# P(blank) = 40/64 = 10/16
checkers = []
10.times { |i| checkers << 'b' }
3.times { |i| checkers << red_checkers[prng.rand(p)] }
3.times { |i| checkers << black_checkers[prng.rand(p)] }

k = checkers.size

8.times do |i|
  8.times { |j| print "#{checkers[ prng.rand(k) ]} " }
  print "\n"
end

test1.txt

b b b b b b RC b 
b b BC BC b BC RC b 
b b b b b RC b RC 
BK RC RC RC b b b b 
b b RC RC b BC b b 
RC b b RC b b BC RC 
b b BC b b b b RC 
b b b RC RC RC b b 

test2.txt

b b b BC b BC b b 
BC b BC RC BC RC RC RC 
BC b BC b RC b RC b 
b BC b b RC BC b RC 
RC b b b RC b b b 
b b b b b BC b BC 
b b b RC b b b b 
RC b b b b BC b b 

test3.txt

RC BC BC RC b b b RK 
RC b b b RC b BC b 
b RC b b b RC b b 
b b BC b b b RK b 
b BC RC b RK b RC b 
b b RC BC b RC b b 
b b b BC b BC b b 
RC RK b b b b BC BC