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+# 464. Can I Win
+
+"""
+in the 100 game two players take turns adding, to a running total, any
+integer from 1 to 10. the player who first causes the running total to reach
+or exceed 100 wins. what if we change the same so that players cannot re-use
+integers? for example, two players might take turns drawing from a common
+pool of numbers from 1 to 15 without replacement until they reach a total >=
+100. given two integers 'maxChoosableInteger' nad 'desiredTotal', return true
+if the first player to move can force a win, otherwise, return false. assume
+both players play optimally.
+"""
+
+
+class Solution(object):
+ def canIWin(self, maxChoosableInteger, desiredTotal):
+ """
+ :type maxChoosableInteger: int
+ :type desiredTotal: int
+ :rtype: bool
+ """
+
+ def get_sum(num):
+ i, curr = 1, 0
+ while i <= 20 and num:
+ if num & 1:
+ curr += i
+ i += 1
+ i >>= 1
+ return curr
+
+ def dfs(pick, player):
+ curr = get_sum(pick)
+ for i in range(maxChoosableInteger):
+ if pick & (1 << i):
+ continue
+ if curr + i + 1 >= desiredTotal or not dfs(pick | (1 << i), player ^ 1):
+ return True
+ return False
+
+ return dfs(0, 0)
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ print(obj.canIWin(maxChoosableInteger=10, desiredTotal=11))
+ print(obj.canIWin(maxChoosableInteger=10, desiredTotal=0))
+ print(obj.canIWin(maxChoosableInteger=10, desiredTotal=1))