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Checkpoint · revision 1

Recursion, Backtracking & DP Checkpoint

Check whether you can read a call tree, prune a search, and replace repeated subproblems with stored results.

Scenario

A recursive solution is correct on small inputs but repeats the same states and becomes unusably slow.

Scored questions

Question 1

What prevents a well-formed recursive function from calling itself forever?

Question 2

Memoization improves naive Fibonacci recursion mainly by:

Question 3

In the N-Queens search, what must happen after a chosen queen leads to a dead end?

Question 4

A standard edit-distance cell uses how many neighbouring predecessor cells when the characters differ?

Answer keys, scoring tolerance, XP, and awards stay on the server. Retrying the same attempt cannot award twice.