LeetCode 72 Edit Distance - State Design

Define $dp[i][j]$ as the minimum operations to convert A[0..i-1] to B[0..j-1]. Base cases differ from LCS: $dp[0][j] = j$: Converting empty string to B[0..j] requires $j$ insertions. $dp[i][0] = i$: Converting A[0..i] to empty string requires $i$ deletions.

These non-zero base cases reflect that converting to/from empty strings has a cost. Unlike LCS, base cases here are non-zero: converting to or from an empty string costs exactly the other string's length.