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* Review the EN heading format. * Fix pythontutor headings. * Fix pythontutor headings. * bug fixes * Fix headings in **/summary.md * Revisit the CN-to-EN translation for Python code using Claude-4.5 * Revisit the CN-to-EN translation for Java code using Claude-4.5 * Revisit the CN-to-EN translation for Cpp code using Claude-4.5. * Fix the dictionary. * Fix cpp code translation for the multipart strings. * Translate Go code to English. * Update workflows to test EN code. * Add EN translation for C. * Add EN translation for CSharp. * Add EN translation for Swift. * Trigger the CI check. * Revert. * Update en/hash_map.md * Add the EN version of Dart code. * Add the EN version of Kotlin code. * Add missing code files. * Add the EN version of JavaScript code. * Add the EN version of TypeScript code. * Fix the workflows. * Add the EN version of Ruby code. * Add the EN version of Rust code. * Update the CI check for the English version code. * Update Python CI check. * Fix cmakelists for en/C code. * Fix Ruby comments
53 lines
2.0 KiB
Python
53 lines
2.0 KiB
Python
"""
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File: binary_search.py
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Created Time: 2022-11-26
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Author: timi (xisunyy@163.com)
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"""
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def binary_search(nums: list[int], target: int) -> int:
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"""Binary search (closed interval)"""
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# Initialize closed interval [0, n-1], i.e., i, j point to the first and last elements of the array
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i, j = 0, len(nums) - 1
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# Loop, exit when the search interval is empty (empty when i > j)
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while i <= j:
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# In theory, Python numbers can be infinitely large (depending on memory size), no need to consider large number overflow
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m = (i + j) // 2 # Calculate midpoint index m
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if nums[m] < target:
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i = m + 1 # This means target is in the interval [m+1, j]
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elif nums[m] > target:
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j = m - 1 # This means target is in the interval [i, m-1]
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else:
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return m # Found the target element, return its index
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return -1 # Target element not found, return -1
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def binary_search_lcro(nums: list[int], target: int) -> int:
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"""Binary search (left-closed right-open interval)"""
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# Initialize left-closed right-open interval [0, n), i.e., i, j point to the first element and last element+1
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i, j = 0, len(nums)
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# Loop, exit when the search interval is empty (empty when i = j)
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while i < j:
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m = (i + j) // 2 # Calculate midpoint index m
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if nums[m] < target:
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i = m + 1 # This means target is in the interval [m+1, j)
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elif nums[m] > target:
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j = m # This means target is in the interval [i, m)
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else:
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return m # Found the target element, return its index
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return -1 # Target element not found, return -1
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"""Driver Code"""
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if __name__ == "__main__":
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target = 6
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nums = [1, 3, 6, 8, 12, 15, 23, 26, 31, 35]
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# Binary search (closed interval)
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index = binary_search(nums, target)
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print("Index of target element 6 =", index)
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# Binary search (left-closed right-open interval)
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index = binary_search_lcro(nums, target)
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print("Index of target element 6 =", index)
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