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LC 1143 Longest Common Subsequence is the foundational sequence DP problem at every FAANG company. Master the 2D recurrence, space-optimize to O(n), and learn how to reconstruct the actual LCS — skills that transfer directly to Edit Distance, Shortest Common Supersequence, and Diff algorithms.
LC 72 Edit Distance (Levenshtein Distance) is the hard-level sequence DP benchmark at Google, Amazon, and Meta. Master the 3-operation recurrence, space-optimize to O(n), and understand how this algorithm powers spell-checkers, DNA alignment, and autocomplete systems.
LC 1092 Shortest Common Supersequence combines LCS computation with DP table reconstruction to produce the actual shortest string containing both inputs as subsequences. A hard-level 2D DP problem asked at Google and Amazon that demands both algorithm depth and reconstruction skill.
LC 312 Burst Balloons is the classic hard-level interval DP problem asked at Google, Amazon, and Meta. The key insight is thinking in reverse — instead of choosing which balloon to burst first, choose which one to burst last in each interval. This transforms an impossible ordering problem into clean O(n^3) DP.
LC 121 Best Time to Buy and Sell Stock is the foundational stock DP problem at every FAANG company. While solvable with a one-pass greedy approach, understanding its state machine formulation (hold/not-hold states) unlocks the full stock problem series from LC 122 through LC 714.