restructuring solutions for spec usage

crystal/euler.cr

@@ -3,11 +3,14 @@
 require "big"
 
 module Euler
-  alias NumType = Int32 | Int64 | UInt32 | UInt64 | BigInt
+  extend self
 
-  def self.trial_division(n : NumType)
-    factors = [] of NumType
-    check = ->(p: NumType) {
+  alias NumType = Int32 | Int64 | UInt32 | UInt64
+
+  macro trial_division_method(given_type)
+    def trial_division(n : {{given_type}})
+      factors = [] of {{given_type}}
+      check = ->(p: {{given_type}}) {
         q, r = n.divmod(p)
         while r.zero?
           factors << p
@@ -28,9 +31,11 @@ module Euler
       factors << n if n > 1
       factors
     end
+  end
 
-  def self.prime_factorization(n : NumType)
-    result = {} of NumType => NumType
+  macro prime_factorization_method(given_type)
+    def prime_factorization(n : {{given_type}})
+      result = {} of {{given_type}} => Int32
       factors = self.trial_division(n)
 
       factors.each do |f|
@@ -44,16 +49,33 @@ module Euler
 
       result
     end
-
-  def self.palindrome?(x)
-    x.to_s.reverse == x.to_s
   end
 
-  def self.to_digit_list(n : NumType)
+  macro to_digit_list_method(given_type)
+    def to_digit_list(n : {{given_type}})
       n.to_s.chars.map { |d| d.to_i }
     end
+  end
 
-  def self.to_big_ints(num_list : Array(NumType))
+  macro to_big_ints_method(given_type)
+    def to_big_ints(num_list : Array({{given_type}}))
       num_list.map { |n| BigInt.new(n) }
     end
   end
+
+  trial_division_method(NumType)
+  trial_division_method(BigInt)
+
+  prime_factorization_method(NumType)
+  prime_factorization_method(BigInt)
+
+  to_digit_list_method(NumType)
+  to_digit_list_method(BigInt)
+
+  to_big_ints_method(NumType)
+  to_big_ints_method(BigInt)
+
+  def palindrome?(x)
+    x.to_s.reverse == x.to_s
+  end
+end

crystal/euler001.cr

@@ -1 +1,9 @@
-puts (1..999).select { |n| (n % 3 == 0) || (n % 5 == 0) }.sum
+module Euler
+  module Problem001
+    extend self
+
+    def solution
+      (1..999).select { |n| (n % 3 == 0) || (n % 5 == 0) }.sum
+    end
+  end
+end

crystal/euler002.cr

@@ -1,3 +1,7 @@
+module Euler
+  module Problem002
+    extend self
+
     def fibonacci_nums_up_to(n)
       result = [1] of Int32
 
@@ -15,4 +19,8 @@ def fibonacci_nums_up_to(n)
       result
     end
 
-puts fibonacci_nums_up_to(4000000).select{ |n| n.even? }.sum
+    def solution
+      fibonacci_nums_up_to(4000000).select{ |n| n.even? }.sum
+    end
+  end
+end

crystal/euler003.cr

@@ -1,3 +1,11 @@
 require "./euler"
 
-puts Euler.trial_division(600851475143).max
+module Euler
+  module Problem003
+    extend self
+
+    def solution
+      Euler.trial_division(600851475143).max
+    end
+  end
+end

crystal/euler004.cr

@@ -1,7 +1,15 @@
 require "./euler"
 
+module Euler
+  module Problem004
+    extend self
+
     def products_of_three_digit_nums
       (100..999).to_a.combinations(2).map { |p| p.product }
     end
 
-puts products_of_three_digit_nums.select { |x| Euler.palindrome?(x) }.max
+    def solution
+      products_of_three_digit_nums.select { |x| Euler.palindrome?(x) }.max
+    end
+  end
+end

crystal/euler005.cr

@@ -1,5 +1,9 @@
 require "./euler"
 
+module Euler
+  module Problem005
+    extend self
+
     def integer_factorization_divisible_by_all_up_to(n)
       result = {} of Euler::NumType => Euler::NumType
       (2..n).map do |i|
@@ -16,4 +20,8 @@ def factors_to_int(factorization : Hash(Euler::NumType, Euler::NumType))
       factorization.map { |prime, exponent| prime ** exponent }.product
     end
 
-puts factors_to_int(integer_factorization_divisible_by_all_up_to(20))
+    def solution
+      factors_to_int(integer_factorization_divisible_by_all_up_to(20))
+    end
+  end
+end

crystal/euler006.cr

@@ -1 +1,9 @@
-puts (1..100).sum ** 2 - (1..100).map { |n| n * n }.sum
+module Euler
+  module Problem006
+    extend self
+
+    def solution
+      (1..100).sum ** 2 - (1..100).map { |n| n * n }.sum
+    end
+  end
+end

crystal/euler007.cr

@@ -1,3 +1,11 @@
-require "./euler"
+require "./prime"
 
-puts Euler.eratosthenes_sieve(1000000)[10000]
+module Euler
+  module Problem007
+    extend self
+
+    def solution
+      Euler::Prime.new.skip(10000).next
+    end
+  end
+end

crystal/euler008.cr

@@ -1,10 +1,15 @@
 require "./euler"
 
+module Euler
+  module Problem008
+    extend self
+
     def largest_consecutive_product(n, adjacent)
       Euler.to_big_ints(Euler.to_digit_list(n)).each_cons(adjacent).map { |x| x.product }.max
     end
 
-puts largest_consecutive_product(
+    def solution
+      largest_consecutive_product(
       BigInt.new("73167176531330624919225119674426574742355349194934
       96983520312774506326239578318016984801869478851843
       85861560789112949495459501737958331952853208805511
@@ -25,3 +30,6 @@ BigInt.new("73167176531330624919225119674426574742355349194934
       84580156166097919133875499200524063689912560717606
       05886116467109405077541002256983155200055935729725
       71636269561882670428252483600823257530420752963450"), 13)
+    end
+  end
+end

crystal/euler009.cr

@@ -1,5 +1,9 @@
 require "./euler"
 
+module Euler
+  module Problem009
+    extend self
+
     def generate_pythagorean_triples(upper_bound)
       ([] of Array(Euler::NumType)).tap do |triples|
         (2..upper_bound).each do |a|
@@ -11,4 +15,8 @@ def generate_pythagorean_triples(upper_bound)
       end
     end
 
-puts generate_pythagorean_triples(500).find([-1]) { |x| x.sum == 1000 }.product
+    def solution
+      generate_pythagorean_triples(500).find([-1]) { |x| x.sum == 1000 }.product
+    end
+  end
+end

crystal/euler010.cr

@@ -1,4 +1,12 @@
 require "./prime"
 
+module Euler
+  module Problem010
+    extend self
+
+    def solution
       prime = Euler::Prime.new
-puts prime.take_while { |x| x < 2000000 }.sum
+      prime.take_while { |x| x < 2000000 }.sum
+    end
+  end
+end

crystal/prime.cr

@@ -2,7 +2,8 @@ require "./euler"
 
 module Euler
   class Prime
-    include Iterator(NumType)
+    # needs to include BigInt ...
+    include Iterator(NumType | BigInt)
 
     def initialize()
       @sieve_size = 16

crystal/spec/euler001_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler001"
+
+describe Euler::Problem001 do
+  it "should return 233168" do
+    Euler::Problem001.solution.should eq 233168
+  end
+end

crystal/spec/euler002_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler002"
+
+describe Euler::Problem002 do
+  it "should return 4613732" do
+    Euler::Problem002.solution.should eq 4613732
+  end
+end

crystal/spec/euler003_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler003"
+
+describe Euler::Problem003 do
+  it "should return 6857" do
+    Euler::Problem003.solution.should eq 6857
+  end
+end

crystal/spec/euler004_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler004"
+
+describe Euler::Problem004 do
+  it "should return 906609" do
+    Euler::Problem004.solution.should eq 906609
+  end
+end

crystal/spec/euler005_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler005"
+
+describe Euler::Problem005 do
+  it "should return 232792560" do
+    Euler::Problem005.solution.should eq 232792560
+  end
+end

crystal/spec/euler006_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler006"
+
+describe Euler::Problem006 do
+  it "should return 25164150" do
+    Euler::Problem006.solution.should eq 25164150
+  end
+end

crystal/spec/euler007_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler007"
+
+describe Euler::Problem007 do
+  it "should return 104743" do
+    Euler::Problem007.solution.should eq 104743
+  end
+end

crystal/spec/euler008_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler008"
+
+describe Euler::Problem008 do
+  it "should return 23514624000" do
+    Euler::Problem008.solution.should eq 23514624000
+  end
+end

crystal/spec/euler009_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler009"
+
+describe Euler::Problem009 do
+  it "should return 31875000" do
+    Euler::Problem009.solution.should eq 31875000
+  end
+end

crystal/spec/euler010_spec.cr

@@ -0,0 +1,8 @@
+require "spec"
+require "../euler010"
+
+describe Euler::Problem010 do
+  it "should return 142913828922" do
+    Euler::Problem010.solution.should eq 142913828922
+  end
+end