update

Author: ncdhz

code/1991.找到数组的中间位置.py

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+#
+# @lc app=leetcode.cn id=1991 lang=python3
+#
+# [1991] 找到数组的中间位置
+#
+
+# @lc code=start
+class Solution:
+ def findMiddleIndex(self, nums: List[int]) -> int:
+ s = sum(nums)
+ r = 0
+ for i in range(len(nums)):
+ n = nums[i]
+ s -= n
+ if r == s:
+ return i
+ r += n 
+ return -1
+# @lc code=end

code/724.寻找数组的中心下标.py

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+#
+# @lc app=leetcode.cn id=724 lang=python3
+#
+# [724] 寻找数组的中心下标
+#
+
+# @lc code=start
+class Solution:
+ def pivotIndex(self, nums: List[int]) -> int:
+ s = sum(nums)
+ r = 0
+ for i in range(len(nums)):
+ n = nums[i]
+ s -= n
+ if r == s:
+ return i
+ 
+ r += n
+ return -1
+# @lc code=end

code/728.自除数.py

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+#
+# @lc app=leetcode.cn id=728 lang=python3
+#
+# [728] 自除数
+#
+
+# @lc code=start
+class Solution:
+ 
+ numbers = set()
+
+ def _selfDividingNumbers(self, n):
+ if n in Solution.numbers:
+ return True
+ 
+ i = n % 10
+ j = n // 10
+
+ while i or j:
+ if i == 0 or n % i != 0:
+ return False
+
+ i = j % 10 
+ j = j // 10
+
+ Solution.numbers.add(n)
+
+ return True
+
+ def selfDividingNumbers(self, left: int, right: int) -> List[int]:
+ 
+ res = []
+ for i in range(left, right + 1):
+ if self._selfDividingNumbers(i):
+ res.append(i)
+ 
+ return res
+# @lc code=end
+