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)}")