DIC = Hash[
  (Array("0".."9") + Array("A".."Z")).
  map.with_index.to_a
]

def conv(s, b=36)
  s.chars.reverse.
    map.with_index{|c, i| DIC[c] * b ** i}.
    reduce(&:+)
end

gets.to_i.times.
  map{ gets.chomp }.
  min_by{|s| conv(s) }.
  tap{|min| p conv(min, DIC[min.chars.max].succ) }