Section Recap

Look at what you can do now:

$1.$ Resource tracking DP (Red Green Towers): $dp[i][j]$ = answer after $i$ steps using $j$ of some resource.

$2.$ Grid DP (Grid 1): $dp[i][j]$ = answer for cell at row $i$, column $j$.

$3.$ String DP (Edit Distance): $dp[i][j]$ = answer comparing first $i$ characters of one string to first $j$ of another. The same 2D table structure, but the indices mean completely different things. Recognizing which pattern fits your problem is the key skill. In the next section, you'll work through Knapsack problems, a special case of resource tracking DP.