Logan, Author at Only Code

Best Time to Buy and Sell Stock [Interview Question]

You are given an array prices where prices[i] is the price of a given stock on the ith day. Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0.

Arrays, Interview Questions

Determine if two trees are same in C++ – LeetCode Solution [Easy]

Given the roots of two binary trees p and q, write a function to check if they are the same or not.
Two binary trees are considered the same if they are structurally identical, and each identical node has the same value.

Trees

Find the Minimum Depth of Binary Tree in C++ – LeetCode Solution [Easy]

Given a binary tree, find its minimum depth.
The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.
Note: A leaf is a node with no children.

Trees

Convert Sorted Array to Binary Search Tree in C++ – LeetCode Solution [Easy]

Given an integer array nums where the elements are sorted in ascending order, convert it to a height-balanced binary search tree.

Arrays, Trees

Add Binary numbers in C++ – LeetCode Solution [Easy]

This problem could be solved in O(N) time complexity, where N is the maximum of the given two strings length. We could start traversing the two strings from the last and keep calculating the sum of each string’s character ie ‘0’ and ‘1’. If there’s a carry propagate it to the sum of the next digits in iteration.

Competitive Programming

How to find the intersection point of two linked lists?

Given the head pointers (head1 and head2) of two linked lists, find the intersection node of the two lists.

Linked Lists

C++ Standard Template Library (STL) – [Stack and Queue]

Stacks and queues are data structures that store elements of a specific data type. They have various operations (methods/functions) to input, output and manage the data.
Stack implements a last-in, first-out (LIFO) policy on its elements.

C/C++, Queues, Stacks

C++ Standard Template Library (STL) – [Heap]

The Heap data structure is an array that can be viewed as a complete Binary Tree. Each node in the tree corresponds to an element of the array A[].
In this post we will learn about, how to build min/max Heaps using STL.

C/C++, Heaps, Special Data Structures

Rat in the maze | Minimum number of steps

Given a maze with obstacles, find the minimum number of steps the rat needs to take to reach the destination.

Breadth First Search (BFS), Competitive Programming

Print Binary tree in vertical order

Given a Binary tree, print it in vertical order from left to right.
We could solve this problem by performing a breadth-first or level order traversal on the given tree.

Breadth First Search (BFS), Trees