[Ruby] Random Str Gen

#Random Str Generator...
#Simple and effective by Mr. P-teo
#Learning Beginner Ruby

random_range = ('a'..'z').to_a

print "String Length: "
str_len = gets.to_i
random_string = 'String: '

char = 0;
while(char <= str_len)
        rand_number = Random.rand(24)
        random_string = random_string + random_range[rand_number].to_s
        char += 1
end

puts random_string