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Update the callouts for the algorithm problems.

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krahets
2023-05-21 19:58:21 +08:00
parent d95c628eef
commit 24d90931e3
8 changed files with 29 additions and 37 deletions
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6
codes/python/chapter_searching/binary_search_edge.py
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@ -12,11 +12,11 @@ def binary_search_left_edge(nums: list[int], target: int) -> int:
while i <= j:
m = (i + j) // 2 # 计算中点索引 m
if nums[m] < target:
i = m + 1 # 此情况说明 target 在区间 [m+1, j] 中
i = m + 1 # target 在区间 [m+1, j] 中
elif nums[m] > target:
j = m - 1 # 此情况说明 target 在区间 [i, m-1] 中
j = m - 1 # target 在区间 [i, m-1] 中
else:
j = m - 1 # 此情况说明首个小于 target 的元素在区间 [i, m-1] 中
j = m - 1 # 首个小于 target 的元素在区间 [i, m-1] 中
if i == len(nums) or nums[i] != target:
return -1 # 未找到目标元素，返回 -1
return i

24
codes/python/chapter_searching/binary_search_rotation.py
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@ -1,24 +0,0 @@
def binary_search_rotation(nums: list[int]) -> int:
"""二分查找左边界（双闭区间）"""
# 初始化双闭区间 [0, n-1] ，即 i, j 分别指向数组首元素、尾元素
i, j = 0, len(nums) - 1
while True:
m = (i + j) // 2 # 计算中点索引 m
if nums[m] < nums[j]:
j = m # 此情况说明 target 在区间 [m+1, j] 中
elif nums[m] > nums[j]:
i = m + 1 # 此情况说明 target 在区间 [i, m-1] 中
else:
return i # 此情况说明 i == j == m ，找到旋转点
"""Driver Code"""
if __name__ == "__main__":
nums: list[int] = [23, 67, 70, 92, 1, 3, 6, 8, 12, 15]
# 二分查找左边界
index_left = binary_search_rotation(nums)
print("数组旋转点的索引 = ", index_left)