This problem is similar to “Search a 2D matrix”, the solution to which I have written in my previous article. If you have read the previous article, read the problem description and continue to the efficient solution.

Problem Link

Problem Description:

Write an efficient algorithm that searches for a target value in an m…

Link to the problem:

Problem Description

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:

  • Integers in each row are sorted from left to right.
  • The first integer of each row is greater than the last integer of the previous row.

Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.

You must write an algorithm that runs in O(n) time.

Naive Solution:

A naive solution is sorting the given array and then do a linear traversal to find the longest consecutive length. It is an easy…

Problem Link:

Given a triangle array, return the minimum path sum from top to bottom.

For each step, you may move to an adjacent number of the row below. More formally, if you are on index i on the current row, you may move to either index i or index i + 1 on the next row.


If you are at an index “i” in a row, you can move to index “i” or index “i+1” in the next row. So, the minimum value for an index “i” in a row can be obtained by considering index “i-1” or index “i” from the previous row. So, the original triangle matrix is modified top down considering the minimum values from the previous row. Finally, we return the minimum value from the last row.

Problem Link:

Problem Description:

You are given a perfect binary tree where all leaves are on the same level, and every parent has two children. The binary tree has the following definition:

struct Node {
int val;
Node *left;
Node *right;
Node *next;

Populate each next pointer to point to its…

Pruthvik Reddy

Looking for opportunities in software development. Interested in Blockchain, distributed computing and back-end development.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store