Lessons from Edit Distance

Three patterns to remember:

$1.$ More operations means more transitions. LCS has 2 choices, Edit Distance has 3.

$2.$ Base cases change with the problem. LCS starts with 0s, Edit Distance starts with indices.

$3.$ The same 2D (two-dimensional) structure works for many string problems. $dp[i][j]$ with two strings is universal. You've now learned the two pillars of string DP. Apply these patterns when you encounter similar problems.