September 2017 Update

Task/24-game-Solve/CoffeeScript/24-game-solve-1.coffee

@@ -1,87 +0,0 @@
-# This program tries to find some way to turn four digits into an arithmetic
-# expression that adds up to 24.
-#
-# Example solution for 5, 7, 8, 8:
-#    (((8 + 7) * 8) / 5)
-
-
-solve_24_game = (digits...) ->
-  # Create an array of objects for our helper functions
-  arr = for digit in digits
-    {
-      val: digit
-      expr: digit
-    }
-  combo4 arr...
-
-combo4 = (a, b, c, d) ->
-  arr = [a, b, c, d]
-  # Reduce this to a three-node problem by combining two
-  # nodes from the array.
-  permutations = [
-    [0, 1, 2, 3]
-    [0, 2, 1, 3]
-    [0, 3, 1, 2]
-    [1, 2, 0, 3]
-    [1, 3, 0, 2]
-    [2, 3, 0, 1]
-  ]
-  for permutation in permutations
-    [i, j, k, m] = permutation
-    for combo in combos arr[i], arr[j]
-      answer = combo3 combo, arr[k], arr[m]
-      return answer if answer
-  null
-
-combo3 = (a, b, c) ->
-  arr = [a, b, c]
-  permutations = [
-    [0, 1, 2]
-    [0, 2, 1]
-    [1, 2, 0]
-  ]
-  for permutation in permutations
-    [i, j, k] = permutation
-    for combo in combos arr[i], arr[j]
-      answer = combo2 combo, arr[k]
-      return answer if answer
-  null
-
-combo2 = (a, b) ->
-  for combo in combos a, b
-    return combo.expr if combo.val == 24
-  null
-
-combos = (a, b) ->
-  [
-    val: a.val + b.val
-    expr: "(#{a.expr} + #{b.expr})"
-  ,
-    val: a.val * b.val
-    expr: "(#{a.expr} * #{b.expr})"
-  ,
-    val: a.val - b.val
-    expr: "(#{a.expr} - #{b.expr})"
-  ,
-    val: b.val - a.val
-    expr: "(#{b.expr} - #{a.expr})"
-  ,
-    val: a.val / b.val
-    expr: "(#{a.expr} / #{b.expr})"
-  ,
-    val: b.val / a.val
-    expr: "(#{b.expr} / #{a.expr})"
-  ,
-  ]
-
-# test
-do ->
-  rand_digit = -> 1 + Math.floor (9 * Math.random())
-
-  for i in [1..15]
-    a = rand_digit()
-    b = rand_digit()
-    c = rand_digit()
-    d = rand_digit()
-    solution = solve_24_game a, b, c, d
-    console.log "Solution for #{[a,b,c,d]}: #{solution ? 'no solution'}"

Task/24-game-Solve/CoffeeScript/24-game-solve-2.coffee

@@ -1,16 +0,0 @@
-> coffee 24_game.coffee
-Solution for 8,3,1,8: ((1 + 8) * (8 / 3))
-Solution for 6,9,5,7: (6 - ((5 - 7) * 9))
-Solution for 4,2,1,1: no solution
-Solution for 3,5,1,3: (((3 + 5) * 1) * 3)
-Solution for 6,4,1,7: ((7 - (4 - 1)) * 6)
-Solution for 8,1,3,1: (((8 + 1) - 1) * 3)
-Solution for 6,1,3,3: (((6 + 1) * 3) + 3)
-Solution for 7,1,5,6: (((7 - 1) * 5) - 6)
-Solution for 4,2,3,1: ((3 + 1) * (4 + 2))
-Solution for 8,8,5,8: ((5 * 8) - (8 + 8))
-Solution for 3,8,4,1: ((1 - (3 - 8)) * 4)
-Solution for 6,4,3,8: ((8 - (6 / 3)) * 4)
-Solution for 2,1,8,7: (((2 * 8) + 1) + 7)
-Solution for 5,2,7,5: ((2 * 7) + (5 + 5))
-Solution for 2,4,8,9: ((9 - (2 + 4)) * 8)