June 2018 Update

Task/24-game-Solve/Python/24-game-solve-2.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+import operator
+from itertools import product, permutations
+
+def mydiv(n, d):
+    return n / d if d != 0 else 9999999
+
+syms = [operator.add, operator.sub, operator.mul, mydiv]
+op = {sym: ch for sym, ch in zip(syms, '+-*/')}
+
+def solve24(nums):
+    for x, y, z in product(syms, repeat=3):
+        for a, b, c, d in permutations(nums):
+            if round(x(y(a,b),z(c,d)),5) == 24:
+                return f"({a} {op[y]} {b}) {op[x]} ({c} {op[z]} {d})"
+            elif round(x(a,y(b,z(c,d))),5) == 24:
+                return f"{a} {op[x]} ({b} {op[y]} ({c} {op[z]} {d}))"
+            elif round(x(y(z(c,d),b),a),5) == 24:
+                return f"(({c} {op[z]} {d}) {op[y]} {b}) {op[x]} {a}"
+            elif round(x(y(b,z(c,d)),a),5) == 24:
+                return f"({b} {op[y]} ({c} {op[z]} {d})) {op[x]} {a}"
+    return '--Not Found--'
+
+if __name__ == '__main__':
+    #nums = eval(input('Four integers in the range 1:9 inclusive, separated by commas: '))
+    for nums in [
+        [9,4,4,5],
+        [1,7,2,7],
+        [5,7,5,4],
+        [1,4,6,6],
+        [2,3,7,3],
+        [8,7,9,7],
+        [1,6,2,6],
+        [7,9,4,1],
+        [6,4,2,2],
+        [5,7,9,7],
+        [3,3,8,8],  # Difficult case requiring precise division
+            ]:
+        print(f"solve24({nums}) -> {solve24(nums)}")

Task/24-game-Solve/Python/24-game-solve-3.py

@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# Python 3
+from operator import mul, sub, add
+
+
+def div(a, b):
+    if b == 0:
+        return 999999.0
+    return a / b
+
+ops = {mul: '*', div: '/', sub: '-', add: '+'}
+
+def solve24(num, how, target):
+    if len(num) == 1:
+        if round(num[0], 5) == round(target, 5):
+            yield str(how[0]).replace(',', '').replace("'", '')
+    else:
+        for i, n1 in enumerate(num):
+            for j, n2 in enumerate(num):
+                if i != j:
+                    for op in ops:
+                        new_num = [n for k, n in enumerate(num) if k != i and k != j] + [op(n1, n2)]
+                        new_how = [h for k, h in enumerate(how) if k != i and k != j] + [(how[i], ops[op], how[j])]
+                        yield from solve24(new_num, new_how, target)
+
+tests = [
+         [1, 7, 2, 7],
+         [5, 7, 5, 4],
+         [1, 4, 6, 6],
+         [2, 3, 7, 3],
+         [1, 6, 2, 6],
+         [7, 9, 4, 1],
+         [6, 4, 2, 2],
+         [5, 7, 9, 7],
+         [3, 3, 8, 8],  # Difficult case requiring precise division
+         [8, 7, 9, 7],  # No solution
+         [9, 4, 4, 5],  # No solution
+            ]
+for nums in tests:
+    print(nums, end=' : ')
+    try:
+        print(next(solve24(nums, nums, 24)))
+    except StopIteration:
+        print("No solution found")