Prefix Sums & Greedy

Several of the array problems Intuit asks share one habit. Each walks the array once or twice and carries a single value forward, like a running product or the most times the next letter may still appear. The product problem, where each slot gets the product of every other value, has come up in an SDE-2 Assessor round, an intern first round and two campus drives. The best contiguous sum came up on a Software Engineer 2 phone screen as Kadane's algorithm followed by a variation. In one SDE-2 interview, the craft coding round opened with a letter-frequency puzzle framed as a musical play.

The hard part usually comes after the first answer runs. On the product problem, division gets banned. On the contiguous-sum problem, the sum alone isn't enough, and you also have to give back where the best run starts and ends. None of these needs a clever data structure, so you're scored on whether the scan handles its edge cases and whether you can explain why each line is correct, including the greedy sort.

The Intuit angle

Expect the constraint to move once your first version works, and shape the code so the change is small. In one round on the product problem, a candidate divided the total product by each value with a guard for zero, and the interviewer took division away with a remark about a very poor compiler. A campus panel walked the same problem through four approaches, from quadratic down to constant extra space, and another asked about overflow and zeros. In Java, have long results from int inputs ready, and give the overflow reason before the Assessor asks for it.

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