input = gets.chomp
output = []
max = 0

matches = input.scan(/(.*?)(ｗ+)/)

matches.each do |md|
  size = md[1].size
  next if md[0].size == 0
  if size > max
    max = size
    output = [md[0]]
  elsif size == max
    output << md[0]
  end
end

puts output