Author Archives: Stanislav_Panteleev

✅ Short Answer: Because LinkedList is both: A sequential list of elements (like an array), AND a double-ended queue (deque). So, Java designers made LinkedList implement both List and Deque interfaces to give us the best of both worlds.

✅ The correct answer is: Deque extends Queue Why? Queue is more general — it defines FIFO behavior. Deque (Double Ended Queue) is more specific, allowing insertion/removal at both ends, so it extends the basic Queue contract.

Let’s dive into the interfaces Queue and Deque in Java — both are part of the java.util package and extend the Collection interface, but they have different purposes and capabilities.

Let’s clearly compare and describe the two major approaches in backtracking:👉 DFS Binary-style (Include/Exclude) and👉 Loop-style (Iterative Recursive)

https://leetcode.com/problems/subsets/

left shift right shift

https://leetcode.com/problems/largest-combination-with-bitwise-and-greater-than-zero/description/ 🧠 Key Insight: For the bitwise AND of multiple numbers to be greater than 0, they must all share at least one bit set to 1.In other words, there must be at least one bit position where all numbers … Continue reading →

🔍 The fields in ArrayList: You’re asking: Why store size separately, if we already have elementData.length? Let’s break it down. 👇 ✅ Because elementData.length is the capacity, not the actual number of elements. elementData.length → how many slots are allocated … Continue reading →

✅ Adding an element to the middle is generally slower in LinkedList than in ArrayList Wait… what? You might’ve heard that LinkedList is good for insertions — but here’s the full picture:

let’s estimate how much memory is used to store one byte primitive in an ArrayList<Byte>.