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SoFi·Software Engineer·Technical Phone Screen·Intermediate

Intermediate
Jul 2026

Summary

SoFi coding screen with a word-wrapping problem that's basically LeetCode 68 but without the justification step. Pretty straightforward if you've done greedy string problems before.

Questions Asked (1)

Q1

Given an array of words and a maximum line width, pack words greedily into lines so each line stays within the width limit. No need to pad or justify the lines, just return them as-is.

Algorithms & Data Structures
Author's notes

Easier than the classic version since you skip the padding logic entirely.

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AI HintsAI Generated

Suggested Approach

Clarify that 'greedily' means adding words to the current line as long as the total length including single spaces stays within the width limit. Then implement a single-pass solution using a pointer to track the current word and build each line by accumulating words until the next word would exceed the limit. Return the list of lines without any padding or justification.

Pro tip: Explicitly state that you will not add trailing spaces or justify lines, and mention that you'll handle edge cases like a single word longer than the width by placing it on its own line. This shows attention to detail and avoids over-engineering.

1. Clarify requirements and edge cases

Confirm that lines should not be padded or justified, and that words are separated by single spaces. Ask about edge cases: empty array, single word longer than width, and whether words can be split.

2. Define the greedy packing rule

Explain that you will start a new line with the first word, then keep adding the next word if the current line length plus one space plus the next word's length is <= maxWidth. Otherwise, finalize the line and start a new one.

3. Implement with a single pass

Use an index to iterate through the words. For each line, track the current length and a list of words. Add words until the limit is reached, then append the joined line to the result and continue.

4. Handle edge cases

If a word is longer than maxWidth, place it alone on a line (since it cannot fit with others). Ensure the last line is added after the loop ends.

5. Analyze complexity and test

State that the time complexity is O(n) where n is the total number of characters, and space is O(n) for the output. Walk through a small example to verify correctness.

Key Points to Mention

  • Greedy algorithm: always fit as many words as possible on the current line without exceeding maxWidth.
  • Single-pass solution with O(n) time and O(n) space (for output).
  • Edge case: a word longer than maxWidth should be placed on its own line.
  • No padding or justification: lines are returned as-is with single spaces between words.
  • Use of a pointer/index to track progress through the array.
  • Clear variable naming and modular code (e.g., a helper to check if a word fits).

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.