def leven(s,t) return t.size if (s == "") return s.size if (t == "") s1 = s[1..-1] t1 = t[1..-1] s[0] == t[0] ? leven(s1, t1) : 1 + [ leven(s1, t1), leven(s, t1), leven(s1, t ) ].min end puts leven(ARGV[0], ARGV[1])
