Cold recall

Three from the last four units, rebuilt with nothing above them.

Same rules as before. No earlier submissions, no reading the lesson until you have finished or genuinely stalled.

One of these three is a search with undo, one is a traversal with a permanent visited mark, and one needs a heap deciding what comes next. Naming which is which before you type is the point.

Problem· 32 min

Word Search II, cold

You have solved this one before. Rebuild it from scratch without looking at your old submission. If the approach does not come back within a few minutes, that is the signal that it needs another pass.

Problem· 25 min

Pacific Atlantic Water Flow, cold

Problem· 25 min

Swim in Rising Water, cold

Checkpoint: recursion and graphs

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Checkpoint: recursion and graphsLesson 1 of 3About 85 min

Cold recall

Three from the last four units, rebuilt with nothing above them.

Same rules as before. No earlier submissions, no reading the lesson until you have finished or genuinely stalled.

One of these three is a search with undo, one is a traversal with a permanent visited mark, and one needs a heap deciding what comes next. Naming which is which before you type is the point.

Problem· 32 min

Word Search II, cold

Problem· 25 min

Pacific Atlantic Water Flow, cold

Problem· 25 min