DSA
Keep each unique element at most twice in-place. Optimal — Time O(n), Space O(1).
Covers: Naive, Optimal (circular link). Optimal — Time O(n), Space O(1).
5 approaches incl. Brute Force, Better, Optimized Approach: SLiding…, and more. Optimal — Time O(n), Space O(1).
Covers: Btute Force, Optimal - Sliding Window. Optimal — Time O(n), Space O(1).
4 approaches incl. BRUTE FORCE, DP, TWO POINTER, and more.
Covers: Using dummy node, Approach2: Recursive Merge. Optimal — Time O(m+n), Space O(m+n).
PrefixSum + Hashmap approach. Optimal — Time O(n), Space O(n).
Covers: Prefixsum + Hashmap, Sliding window. Optimal — Time O(n), Space O(1).
Covers: Extra Space (Naive), Two Pointers from End (Optim…, Gap Method (Shell Sort idea). Optimal — Space O(m + n).
Arrays problem — solution with code and analysis.
Covers: Brute Force, Two pointer. Optimal — Time O(n), Space O(1).
Covers: brute Force, Two pointer. Optimal — Time O(n), Space O(1).
Arrays. Time O(nlogn + mlogm), Space O(1).
Covers: Brute Force, Optimal. Optimal — Time O(n), Space O(n).
Covers: Brute Force, Better, Optimal. Optimal — Time O(n), Space O(n).
Two Pointer approach. Optimal — Time O(n), Space O(1).