Three patterns to remember from LCS:
Two sequences means 2D (two-dimensional) DP. Track progress in both with .
Match vs skip is the core decision. Match gives diagonal +1, skip gives max of top or left.
Many problems reduce to LCS. "Minimum deletions to make strings equal" = . Next, you'll see Edit Distance, where you have three operations instead of just skip. Apply these patterns when you encounter similar problems.