#!/usr/bin/ruby -w
# Given two filenames specified on the command line, replace the whitespace
# characters from the first file with the corresponding characters from
# the second file.

if ARGV.size != 2
   print "#{$0} {layer1.txt} {layer2.txt}\n"
   exit 1
end

data1 = nil
data2 = nil
File.open(ARGV[0], "r") {|f| data1 = f.read}
File.open(ARGV[1], "r") {|f| data2 = f.read}
if data1.size != data2.size
   print "File sizes are not equal: #{data1.size} vs #{data2.size}\n"
   exit 1
end

space = /\s/
data1.chars.zip(data2.chars).each{|p|
   print p[space.match?(p[0]) ? 1 : 0]
}