anagram.rb

file = File.open('/usr/share/dict/words').read

lines = file.lines

$words = lines.map do |word|
    word.strip.downcase
end


def is_anagram(word, word2)
    word.split('').sort.join == word2.split('').sort.join
end

def find_longest_anagram(words)
    longest = 0
    longest_word = nil

    words.each do |word|
        words.each do |word2|
            if is_anagram(word, word2)
                if word.length > longest
                    longest_word = word
                    longest = word.length
                end
            end
        end
    end

    gets
    longest_word
end

# linear!!
def find_longest_anagram(words)
    longest = 0
    longest_signature = nil

    anagrams = Hash.new { [] }
    words.each do |word|
        signature = word.split('').sort.join
        anagrams[signature] <<= word

        if word.length > longest && anagrams[signature].length > 1
            longest = word.length
            longest_signature = signature
        end
    end

    gets
    anagrams[longest_signature]
end

start = Time.now
puts find_longest_anagram($words).inspect
finish = Time.now
puts "Took #{finish - start} seconds"

division.rb

# integer division
# WITHOUT using * or / operators (and no % either)
# return result, remainder


def divide(number, divisor)
    result = 0

    while number > divisor
        result += max(1, result)
        divisor += divisor
        number -= divisor
    end

    remainder = number
    
    return result, remainder
end


start = Time.now
puts divide(110000000, 3)
finish = Time.now
puts "Took #{finish - start} seconds"

spellcheck.rb

file = File.open('/usr/share/dict/words').read

lines = file.lines

$words = lines.map do |word|
    word.strip.downcase
end

$words = ["asd", "ertert", "k4l534lk5"]


def spellcheck_slow(word)
    # true if in dictionary
    # false if not
    iter = 0
    $words.each do |dict_word|
        if word == dict_word
            puts "#{iter} iterations"
            return true
        end
        iter += 1
    end

    puts "#{iter} iterations"
    return false
end


def spellcheck(word, words)
    $iter += 1

    word = word.downcase

    middle = words.length / 2

    if words[middle] == word
        return true
    elsif words[middle] != word && words.length == 1
        return false
    elsif words[middle] > word
        # look in the first half
        words = words[0..middle]
        return spellcheck(word, words)
    elsif words[middle] < word
        # look in the bottom half
        words = words[middle..-1]
        return spellcheck(word, words)
    end

end

start = Time.now
spellcheck_slow("paroxysm")
finish = Time.now
puts "Took #{finish - start} seconds"


$iter = 0
start = Time.now
spellcheck("paroxysm", $words)
finish = Time.now
puts "#{$iter} iterations"
puts "Took #{finish - start} seconds"