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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

List Slicing Programs in Python

[:N] prefix, [-N:] suffix, [::K] every Kth. K=0 is a crash, so the code bails.

BeginnerList ProgramsExample 19 of 25
list-slicing-programs.py
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1# Program to demonstrate list slicing
2

3items = input("Enter list elements separated by space: ").split()
4

5N = int(input("Enter N for first/last N elements: "))
6K = int(input("Enter K for every Kth element: "))
7

8print("First N elements:", items[:N])
9print("Last N elements:", items[-N:])
10print("Every Kth element:", items[::K] if K != 0 else "K cannot be 0")

Output

Enter list elements separated by space: a b c d e f
Enter N for first/last N elements: 2
Enter K for every Kth element: 2
First N elements: ['a', 'b']
Last N elements: ['e', 'f']
Every Kth element: ['a', 'c', 'e']

What's going on

items[:2] first two. items[-2:] last two. items[::2] every second item starting at 0.

items[::0] raises ValueError. The if K != 0 is not being fancy. Slice step 0 is illegal.

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