🔗LC150 🟡 Medium 🧩 Pattern – Stack You are given an array of strings tokens that represents an arithmetic expression in a Reverse Polish Notation. Evaluate the expression. Return an integer that represents the value of the expression. Note that: Example Solution We use a stack to keep track of… Read More »Evaluate Reverse Polish Notation – 150
Given, an arithmetic expression. We need to Evaluate Postfix Expression, also known as Reverse Polish Notation. Operators include /,*,+,- and we will always return a finite result, there won’t be any divide with zero operations. Example What is a Postfix Expression A Postfix Expression or a Reverse Polish Notation is… Read More »Program to Evaluate Postfix Expression – LeetCode
We have an expression that contains brackets and alphanumeric characters, and we need to check whether the parenthesis are balanced or not. Balanced Parenthesis means an equal number of opening and closing brackets. Example Solution Approach – Using Stack Why Stack Data Structure? Here, our priority is to find if… Read More »Balanced Parenthesis Program
I was brushing up my data structure skills and this post contains code for the Stack program using both Array and STL containers, the Stack follows the LIFO mechanism i.e Last In First Out, the element that was inserted last will also be the first to be deleted like a… Read More »Stack Program in C++ using Array and STL