Kth Smallest Number in M Sorted Lists
Explore how to efficiently merge multiple sorted lists to find the kth smallest number among them. Understand handling duplicates as unique elements and learn to return appropriate values when k exceeds total elements or lists are empty.
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Statement
Given a list, lists, containing k, find the
Even if some values appear multiple times across the lists, each occurrence is treated as a unique element when determining the
If k exceeds the total number of elements across all lists, return the largest element among them. If the lists are empty, return 0.
Constraints:
-
lists[i].length -
lists[i][j] -
k
Examples
Understand the problem
Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:
Smallest Number in Sorted Lists
What is the output if the following lists and the value of k are given as input?
list1 = [1, 4, 5]
list2 = [4, 7, 8]
list3 = [2, 6, 9]
k = 5
7
5
6
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Try it yourself
Implement your solution in KthSmallest.cpp in the following coding playground.
#include <iostream>#include <vector>#include <queue>int KSmallestNumber(std::vector<std::vector<int>> list, int k){// Replace this placeholder return statement with your codereturn -1;}