Some algorithm problems solved in Ruby

anagram.rb

def anagram?(string, candidate)
  string.chars.sort == candidate.chars.sort
end

require 'minitest/autorun'

class Test < MiniTest::Test
  def test_anagram
    assert anagram?('beta', 'bate')
    assert anagram?('beta', 'beat')
    refute anagram?('beta', 'back')
  end
end

string_reverse.rb

def string_reverse(string)
  string.chars.reduce { |result, c| c + result }
end

require 'minitest/autorun'

class Test < MiniTest::Test
  def test_string_reverse
    assert_equal 'fedcba', string_reverse('abcdef')
  end
end

string_to_integer.rb

def string_to_integer(string)
  string.chars.reduce(0) { |result, c| (c.ord - '0'.ord) + result * 10 }
end

require 'minitest/autorun'

class Test < MiniTest::Test
  def test_string_to_integer
    assert_equal 12345, string_to_integer('12345')
  end
end