Leetcode # 1198. Find Smallest Common Element in All Rows

Problem

https://leetcode.com/problems/find-smallest-common-element-in-all-rows

Solution: Binary Search

Time Complexity: O(len(mat) * log(len(mat[0])))
Space Complexity: O(1)
(The input and output generally do not count towards the space complexity.)

class Solution:
  def smallestCommonElement(self, mat: List[List[int]]) -> int:
    for n in mat[0]:
      for i in range(1, len(mat)):
        row = mat[i]
        if (_i := bisect.bisect(row, n)) == 0 or row[_i - 1] != n:
          break
        if i == len(mat) - 1:
          return n
    return -1

Last Updated on 2025/08/09 by A1go