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1. Sum of List Elements2. Largest Element in List3. Smallest Element in List4. Count Occurrences in List5. Remove Duplicates from List6. Merge Two Lists7. Intersection of Lists8. Union of Lists9. Sort List10. Reverse List11. Check if List is Sorted12. Find Second Largest Element13. Find N Largest Elements14. Clone / Copy List15. Rotate List16. Remove Empty Lists17. Flatten Nested List18. Find Common Elements of Two Lists19. List Slicing Programs20. Replace List Elements21. Remove Element by Value22. Count Prime Numbers in List23. Pair Sum Problem24. Unique Elements from Both Lists25. List Difference

Replace List Elements in Python

Replace all occurrences of a value in a list with another value.

BeginnerList ProgramsExample 20 of 25
replace-list-elements.py
1# Program to replace list elements
2

3items = input("Enter list elements separated by space: ").split()
4old = input("Enter value to replace: ")
5new = input("Enter new value: ")
6

7replaced = [new if x == old else x for x in items]
8

9print("Updated list:", replaced)

Output

Enter list elements separated by space: a b a c
Enter value to replace: a
Enter new value: z
Updated list: ['z', 'b', 'z', 'c']

What's going on

We use a list comprehension to selectively substitute one value for another.

After this program

If the idea is still fuzzy, read Day 5: Lists and List Methods in the Python course. For a short check, try the Python quiz (300 questions). Stay with all 25 list programs, or see every topic on Python exercises.

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