Question

#This function "binarySearchPythonCode" identifies the elements which is present in the start and end values

def binarySearchPythonCode(list, Element, startElement, endElement):

#Variable which describes whether the element is present or not

isPresent = False

#condition check for start and end values

while startElement<=endElement and not isPresent:

#logic for calculating the mid value

midElement = startElement + endElement//2

# if condition which checks whether the mid value is same as element to be searched

if list[midElement] == Element:

#if condition satisfies it changes the flag to true

isPresent = True

#else condition which displays the end value and start value

else:

# if condition checks whether the element is present in the list or not

if Element < list[midElement]:

#if the element is present it calculates the end value

endElement = midElement-1

#else it will calculate the start value

else:

startElement = midElement+1

# returns the flag bit

return isPresent

list = [10, 20, 30, 40, 50, 60, 70, 80, 90]

print(binarySearchPythonCode(list, 40, 10, 90))

python code gives error, index error, how to fix?

Answer 1

Problem With Code:

=====================

=> Binary search logic is based on index but you are passing start and end elements instead of their indexes.

=> The function is recursive but in current code it calls only once. It is not called recursively after updating firstElement index and endElement.

Updated Solution:

=====================

def binarySearchPythonCode(list, Element, startElement, endElement):

#Variable which describes whether the element is present or not
isPresent = False
#condition check for start and end values
while startElement<=endElement and not isPresent:
#logic for calculating the mid value
midElement = (startElement + endElement) // 2
# if condition which checks whether the mid value is same as element to be searched
if list[midElement] == Element:
#if condition satisfies it changes the flag to true
isPresent = True
#else condition which displays the end value and start value
else:
# if condition checks whether the element is present in the list or not
if Element < list[midElement]:
#if the element is present it calculates the end value
endElement = midElement-1
binarySearchPythonCode(list, Element, startElement, endElement)
#else it will calculate the start value
else:
startElement = midElement+1
binarySearchPythonCode(list, Element, startElement, endElement)
# returns the flag bit
return isPresent

list = [10, 20, 30, 40, 50, 60, 70, 80, 90]

print(binarySearchPythonCode(list, 40, 0, len(list)-1))

Description:

==============

=> The above solution solves the problems that I have mentioned in the beginning.

=> The search for particular element in list using binary search recursively.