Removing the Nth node from the end of a linked list is a perfect warm-up for real-world tasks like trimming logs, pruning history...

Finding not just whether a linked list has a cycle but exactly where that cycle begins is a real-world need whenever you’re dealing with...

Detecting a cycle in a linked list is a classic problem that comes up when you need to guard against infinite loops—whether you’re...

Merging two sorted linked lists is like merging two sorted streams of data—think combining two user event logs in chronological order....

Reversing a linked list is one of those fundamental operations that underpins many real-world tasks—reordering a playlist, undo history,...

When you need to find the one missing entry in a sequence—say missing log IDs, seats, or data packets— Missing Number  is the classic...

Finding the most frequent items in a dataset is a common real-world task—think trending topics in social media, most visited pages on a...

Finding the intersection of two arrays - i.e. the common elements between two lists - is a real-world task you’ll do when reconciling...

Finding the Kth largest element in an array is a practical problem you’ll face when you need to compute statistics on large...

Sorting an array of red, white, and blue objects—represented by 0, 1, and 2—is a classic real-world task when you need to group items by...

Merging two sorted arrays is a super-practical task you’ll do whenever you need to combine sorted streams—think merging log files, time...

The First Bad Version problem - a perfect warm-up to demonstrate binary search

Binary Search is a cornerstone algorithm that shows up in everything from database lookups to system libraries. It’s a perfect warm‑up...

Problem Statement - Search Insert Position Given a sorted array of distinct integers  and a target value , return the index  if the...

Finding the majority element—an item that appears more than half the time in an array—is a classic warm‑up that’s surprisingly useful in...

Finding the longest common prefix among an array of strings is a classic warm‑up. It pops up in real‑world scenarios like building...

I’m staring at my whiteboard, fresh off writing the brute‑force substring search: two nested loops, compare needle at every haystack...

Searching for a substring within a larger string is a fundamental task in many real‑world applications—think text editors, search...

Checking whether a string is a palindrome—ignoring punctuation, spaces, and case—is a classic coding interview warm‑up. It’s directly...

Finding the first non‑repeating character in a string is a great warm‑up that combines practical string processing with frequency...