def testCharsMap(str)
	res = str.chars.map{|c| c == '\\' ? '\\\\' : c }.join
	return res
end

def testRegexp(str)
	res = str.gsub(/\\/, '\\\\\\')
	return res
end


s = "a\\b" * 1000000


t = Time.now
res = testCharsMap(s)
elapsed = Time.now - t

t = Time.now
res2 = testRegexp(s)
elapsed2 = Time.now - t

puts "elapsed charmap: #{elapsed * 1000.0} ms"
puts "elapsed regexp: #{elapsed2 * 1000.0} ms"

#puts "res: #{res}"
#puts "res2: #{res2}"

#puts res.length

#puts "len: #{len}"
#puts "len2: #{len2}"