Debrief

The two adaptations that half of these needed, and what a bad result here means.

Quick check· 5 min

Why hold indexes?

In the parentheses repair, what does a stack of indexes give you that a stack of characters does not?

The positions of the openers that were never matched, which are exactly the characters to deleteFaster lookups, since integers compare more cheaply than charactersThe ability to detect that the string is invalid, which characters alone cannot doA guarantee that the scan is linear rather than quadratic

Select all that apply· 5 min

Sweep or merge?

Select every question that an event sweep answers better than merging the intervals.

The largest number of intervals active at any one momentWhether a running total of weights ever exceeds a limitThe total length covered by at least one intervalThe gaps left uncovered between the earliest start and latest endThe first moment at which at least three are active

Checkpoint: stacks, search, and intervals

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Checkpoint: stacks, search, and intervalsLesson 3 of 3About 18 min

Debrief

The two adaptations that half of these needed, and what a bad result here means.

Quick check· 5 min

Why hold indexes?

In the parentheses repair, what does a stack of indexes give you that a stack of characters does not?

Select all that apply· 5 min

Sweep or merge?

Select every question that an event sweep answers better than merging the intervals.