Time: 134 ms (94.90%), Space: 16.8 MB (98.78%) - LeetHub

Author: hogan-tech

1140-stone-game-ii/1140-stone-game-ii.py

@@ -0,0 +1,47 @@
+# time complexity:O(n^3)
+# space complexity: O(n^2)
+from typing import List
+
+
+class Solution:
+    def stoneGameII(self, piles: List[int]) -> int:
+        memo = [[0] * len(piles) for _ in range(len(piles))]
+        suffixSum = piles[:]
+
+        for i in range(len(suffixSum) - 2, -1, -1):
+            suffixSum[i] += suffixSum[i + 1]
+
+        return self.max_stones(suffixSum, 1, 0, memo)
+
+    def max_stones(
+        self,
+        suffixSum: List[int],
+        maxTillNow: int,
+        currIndex: int,
+        memo: List[List[int]],
+    ) -> int:
+        if currIndex + 2 * maxTillNow >= len(suffixSum):
+            return suffixSum[currIndex]
+
+        if memo[currIndex][maxTillNow] > 0:
+            return memo[currIndex][maxTillNow]
+
+        res = float("inf")
+
+        for i in range(1, 2 * maxTillNow + 1):
+            res = min(
+                res,
+                self.max_stones(
+                    suffixSum,
+                    max(i, maxTillNow),
+                    currIndex + i,
+                    memo,
+                ),
+            )
+
+        memo[currIndex][maxTillNow] = suffixSum[currIndex] - res
+        return memo[currIndex][maxTillNow]
+
+
+piles = [2, 7, 9, 4, 4]
+print(Solution().stoneGameII(piles))