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Checkpoint · revision 1

Array Patterns Checkpoint

Check how two pointers and sliding windows remove repeated work while preserving the problem's constraints.

Scenario

A learner is replacing nested loops with a single pass, but must justify why the replacement is valid.

Scored questions

Question 1

A fixed-size window moves one position right. What is the efficient update?

Question 2

Scanning an array once with two indices usually has which time complexity?

Question 3

For values [3, 1, 4, 2] and window size 2, what is the largest window sum?

Question 4

Why does the classic opposite-end two-pointer sum method normally require sorted input?

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