Linked List Surgery

Reversal gets most of the attention, but many of Qualcomm's linked-list questions are smaller jobs on a list you already hold. Each takes a few lines, and each one tends to break at the head, at the tail or one step past the end. Rounds are often on paper, where nothing warns you that a pointer went stale. So walk each of those edge cases by hand before you call the code done.

Two habits cover most of it. A dummy node in front of the head turns index 0 into an ordinary case, and two pointers moving at different speeds or a fixed gap apart find a position in a single pass. In the practice widget, each list goes in and comes out as an array of values. The solutions show the pointer moves you'd write on the board.

QualcommPremium lesson · Coding round

The 5 Qualcomm problems are below.

1. 1A Premium questionCoding · Medium · Frequently asked
2. 2A Premium questionCoding · Easy
3. 3A Premium questionCoding · Medium

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From 135 Qualcomm reports, forum threads behind logins and write-ups in Chinese.

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