DSA
Trie. Time O(m×k×4^L), Space O(L).
Trie. Space O(m).
Trie. Time O(n² * k), Space O(n²).
Covers: Set, Trie Based. Optimal — Time O(26*L), Space O(nL).
Covers: Brute Force, Trie. Optimal — Time O(N^2), Space O(n).
Using Trie approach. Optimal — Time O(n^2), Space O(n^2).
Trie. Time O(nL), Space O(nL).
Trie problem — solution with code and analysis.
DFS - Backtracking approach. Optimal — Time O(mn * 4^L), Space O(1).