Python/maths/find_max.py at master · TheAlgorithms/Python · GitHub

Name: Python/maths/find_max.py at master · TheAlgorithms/Python · GitHub
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from __future__ importannotations


deffind_max_iterative(nums: list[int|float]) ->int|float:
"""
 >>> for nums in ([3, 2, 1], [-3, -2, -1], [3, -3, 0], [3.0, 3.1, 2.9]):
 ... find_max_iterative(nums) == max(nums)
 True
 True
 True
 True
 >>> find_max_iterative([2, 4, 9, 7, 19, 94, 5])
 94
 >>> find_max_iterative([])
 Traceback (most recent call last):
 ...
 ValueError: find_max_iterative() arg is an empty sequence
 """
iflen(nums) ==0:
raiseValueError("find_max_iterative() arg is an empty sequence")
max_num=nums[0]
forxinnums:
ifx>max_num: # noqa: PLR1730
max_num=x
returnmax_num


# Divide and Conquer algorithm
deffind_max_recursive(nums: list[int|float], left: int, right: int) ->int|float:
"""
 find max value in list
 :param nums: contains elements
 :param left: index of first element
 :param right: index of last element
 :return: max in nums

 >>> for nums in ([3, 2, 1], [-3, -2, -1], [3, -3, 0], [3.0, 3.1, 2.9]):
 ... find_max_recursive(nums, 0, len(nums) - 1) == max(nums)
 True
 True
 True
 True
 >>> nums = [1, 3, 5, 7, 9, 2, 4, 6, 8, 10]
 >>> find_max_recursive(nums, 0, len(nums) - 1) == max(nums)
 True
 >>> find_max_recursive([], 0, 0)
 Traceback (most recent call last):
 ...
 ValueError: find_max_recursive() arg is an empty sequence
 >>> find_max_recursive(nums, 0, len(nums)) == max(nums)
 Traceback (most recent call last):
 ...
 IndexError: list index out of range
 >>> find_max_recursive(nums, -len(nums), -1) == max(nums)
 True
 >>> find_max_recursive(nums, -len(nums) - 1, -1) == max(nums)
 Traceback (most recent call last):
 ...
 IndexError: list index out of range
 """
iflen(nums) ==0:
raiseValueError("find_max_recursive() arg is an empty sequence")
if (
left>=len(nums)
orleft<-len(nums)
orright>=len(nums)
orright<-len(nums)
 ):
raiseIndexError("list index out of range")
ifleft==right:
returnnums[left]
mid= (left+right) >>1# the middle
left_max=find_max_recursive(nums, left, mid) # find max in range[left, mid]
right_max=find_max_recursive(
nums, mid+1, right
 ) # find max in range[mid + 1, right]

returnleft_maxifleft_max>=right_maxelseright_max


if__name__=="__main__":
importdoctest

doctest.testmod(verbose=True)