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🐱(dynamic): 303. 区域和检索 - 数组不可变

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`@@ -1057,6 +1057,39 @@ class Solution:`
`1057`	`1057`	`return len(tails)`
`1058`	`1058`	```
`1059`	`1059`
	`1060`	`+## 303. 区域和检索 - 数组不可变`
	`1061`	`+`
	`1062`	`+[原题链接](https://leetcode-cn.com/problems/range-sum-query-immutable/)`
	`1063`	`+`
	`1064`	`+### 思路`
	`1065`	`+`
	`1066`	`+动态规划前缀和。`
	`1067`	`+`
	`1068`	+```python
	`1069`	`+class NumArray:`
	`1070`	`+`
	`1071`	`+ def __init__(self, nums: List[int]):`
	`1072`	`+ length = len(nums)`
	`1073`	`+ self.sum_nums = [0 for _ in range(length)]`
	`1074`	`+ for i in range(length):`
	`1075`	`+ if i == 0:`
	`1076`	`+ self.sum_nums[i] = nums[i]`
	`1077`	`+ else:`
	`1078`	`+ self.sum_nums[i] = self.sum_nums[i - 1] + nums[i]`
	`1079`	`+`
	`1080`	`+`
	`1081`	`+ def sumRange(self, i: int, j: int) -> int:`
	`1082`	`+ if i == 0:`
	`1083`	`+ return self.sum_nums[j]`
	`1084`	`+ else:`
	`1085`	`+ return self.sum_nums[j] - self.sum_nums[i - 1]`
	`1086`	`+`
	`1087`	`+`
	`1088`	`+# Your NumArray object will be instantiated and called as such:`
	`1089`	`+# obj = NumArray(nums)`
	`1090`	`+# param_1 = obj.sumRange(i,j)`
	`1091`	+```
	`1092`	`+`
`1060`	`1093`	`## 309. 最佳买卖股票时机含冷冻期`
`1061`	`1094`
`1062`	`1095`	`[原题链接](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/)`

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