Touch Typing with Ruby

tt.rb

# tt.rb

def interval ()
    start_time = (Time.now.to_f * 1000).to_i
    lambda {
        end_time = (Time.now.to_f * 1000).to_i
        end_time - start_time
    }
end

def word (level)
    chars = "fjdkslaghvmcxzbnrueiwoqpty;:,./!\"#\$%&'()=[]{}"
    vals = chars.split('')
    n = []
    (0 .. 4).each do
        n << rand(0 .. level)
    end
    w = n.map{|i| vals[i]}
    w.join
end

def problem_line (level)
    w = []
    (0 .. 7).each do
        w << word(level)
    end
    w.join(' ')
end

def difference (problem_line, enter_line)
    vec = problem_line.split('').zip(enter_line.split(''))
    result = vec.map{|v|
        if v[0] == v[1] then
            ' '
        else 
            v[0]
        end
    }
    result.join
end

def count_wrong (diff_line)
    diff_line.length - diff_line.count(' ')
end

def main (initial_level)
    min_level = 2
    if min_level <= initial_level then 
        level = initial_level
    else
        level = min_level
    end
    loop do
        printf("level: %d\n", level)
        problem_line = problem_line(level)
        puts problem_line
        inter = interval
        enter_line = gets
        diff_line = difference(problem_line, enter_line)
        puts diff_line
        wrongs = count_wrong(diff_line)
        if enter_line == "" then
        else
            if wrongs < 2 && inter.call <= 25000 then
                level=level+1
            end
            if 3 <= wrongs then
                if 2 < level then
                    level = level - 1
                end
            end
        end
    end
end

main 2