Maximum Product of Word Lengths

MediumBit Manipulationbit manipulation

Solve this the way you would in the interview: out loud, on a timer, with an AI interviewer asking follow-ups while you code. You get a scored report at the end.

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Problem

Given a list of lowercase words words, pick two words at **different indices** that have no letter in common and compute the product of their lengths. Return the largest such product, or 0 if no pair of words is letter-disjoint. Aim for O(n^2 + L) time where L is the total number of characters: the disjointness check for a pair should take constant time.

Examples

Input: words = ["cat","dog","birds","ox"]
Output: 15
"cat" and "birds" share no letters, giving 3 * 5 = 15. "dog" and "birds" share 'd'.
Input: words = ["aa","a","aaa"]
Output: 0
Every pair shares the letter 'a'.

Constraints

  • 2 <= words.length <= 1000
  • 1 <= words[i].length <= 1000
  • words[i] contains only lowercase English letters

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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