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Python | Remove all occurrences a given element from the list

Here, we are going to implement a Python program that will remove all occurrences a given element from the list.
Submitted by IncludeHelp, on August 06, 2018

Given a list, and we have to remove all occurrences of a given element from the list in Python.

Example:

    Input:
    list = [10, 20, 10, 30, 10, 40, 10, 50]
    n = 10

    Output:
    list after removing 10 from the list
    list = [20, 30, 40, 50]

Logic:

• Run a while loop from 0^th element to last element's index.
• Check the element whether it is equal to the number (which is to be removed) or not.
• If any element of the list is equal to the number (which is to be removed), remove that element from the list.
• To remove the number from the list, use list.remove() method.
• After removing the number/element from the list, decrease the length, because one item is deleted, and then continue the loop to check the next item at same index (because after removing the element – next elements shifts to the previous index.
• If element is not found (i.e. is not removed), then increase the loop counter to check next element.

Example:

# list with integer elements
list = [10, 20, 10, 30, 10, 40, 10, 50]
# number (n) to be removed
n = 10

# print original list 
print ("Original list:")
print (list)

# loop to traverse each element in list
# and, remove elements 
# which are equals to n
i=0 #loop counter
length = len(list)  #list length 
while(i<length):
	if(list[i]==n):
		list.remove (list[i])
		# as an element is removed	
		# so decrease the length by 1	
		length = length -1  
		# run loop again to check element							
		# at same index, when item removed 
		# next item will shift to the left 
		continue
	i = i+1

# print list after removing given element
print ("list after removing elements:")
print (list)

Output

    Original list:
    [10, 20, 10, 30, 10, 40, 10, 50]
    list after removing elements:
    [20, 30, 40, 50]