Maximal Rectangle

HardDynamic ProgrammingMonotonic Stack

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 rows x cols binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area.

Examples

Input: matrix = [["1","0","1","0","0"],["1","0","1","1","1"],["1","1","1","1","1"],["1","0","0","1","0"]]
Output: 6
Input: matrix = [["0"]]
Output: 0
Input: matrix = [["1"]]
Output: 1

Constraints

  • rows == matrix.length
  • cols == matrix[i].length
  • 1 <= rows, cols <= 200
  • matrix[i][j] is '0' or '1'.

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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