Add can_i_win

dotfiles/lib/bin/can_i_win.py

@@ -0,0 +1,69 @@
+def memoize(f):
+    memo = {}
+
+    def helper(*args):
+        args_tuple = tuple(args)
+        if args_tuple not in memo:
+            memo[args_tuple] = f(*args)
+        return memo[args_tuple]
+
+    return helper
+
+
+def can_i_win(max_value, available_numbers):
+    if not isinstance(available_numbers, frozenset):
+        available_numbers = frozenset(available_numbers)
+    return _can_i_win(max_value, available_numbers, 0)
+
+
+@memoize
+def _can_i_win(max_value, available_numbers, current_value):
+    for number in available_numbers:
+        new_value = current_value + number
+        if new_value > max_value:
+            continue
+        new_numbers = available_numbers - frozenset([number])
+        can_win, _ = _can_i_win(max_value, new_numbers, new_value)
+        if not can_win:
+            return (True, number)
+    return (False, list(iter(available_numbers))[0])
+
+
+def play_game(max_value, max_number, computer_parity=0):
+    available_numbers = frozenset(range(max_number))
+    move_count = 0
+    count = 0
+    while True:
+        print("Count is {0}, numbers are {1}, max is {2}".format(
+            count, available_numbers, max_value
+        ))
+        computer_turn = move_count % 2 == computer_parity
+        if move_count % 2 == computer_parity:
+            can_win, number = _can_i_win(max_value, available_numbers, count)
+            print("Computer thinks it can win: {0}".format(can_win))
+        else:
+            number = get_valid_selection(available_numbers)
+        count += number
+        available_numbers -= frozenset([number])
+        move_count += 1
+        print("{0} selected, count is now {1}".format(number, count))
+        if count > max_value:
+            if computer_turn:
+                print("You win")
+            else:
+                print("You lose")
+            return
+        print("------------------------------------------------------")
+
+
+def get_valid_selection(valid_numbers):
+    while True:
+        number = int(input(
+            "Enter one of the following numbers {0}:\n".format(valid_numbers)
+        ))
+        if number in valid_numbers:
+            return number
+
+
+if __name__ == '__main__':
+    play_game(14, 7, computer_parity=1)