C++ does not support functions that return arrays directly because arrays do not have a built-in size or type information that can be returned along with the array. This design choice was made by the C++ creators to avoid memory management issues. But, we have alternative methods to achieve similar result. In this article, we will understand why C++ does not support functions returning arrays and how to overcome this limitation using other techniques. Functions Returning an Array First of all, let's understand what will happen if we try to return an array from a function in C++. Array ... Read More

No, C++ does not support Variable Length Arrays (VLAs). A Variable length array is an array whose size is determined at runtime, not at compile time. These types of arrays are only supported in C99 version of C language. In this article, we will discuss the reasons why C++ does not support VLAs and what alternatives are available for variable array allocation. What is Variable Length Array (VLA)? A Variable Length Array (VLA) is an array whose size can be determined at runtime. It is not supported in standard C++. But, in C99 you can declare a VLA like ... Read More

The delete[] operator is used to deallocate that memory from heap that was allocated using the new[] operator. In this article, we will explore, what is delete[] operator in C++, how it works, and how it knows the size of the operand array to deallocate the correct amount of memory. The delete[] Operator The delete[] operator is a C++ operator that is used to free memory that was previously allocated for an array using the new[] operator. It is always important to deallocate memory that has been allocated with new[] to avoid memory leaks in your program. If you ... Read More

Arrays can be passed to a function as an argument. In this program, we will perform to display the elements of the 2 dimensional array by passing it to a function.AlgorithmBegin The 2D array n[][] passed to the function show(). Call function show() function, the array n (n) is traversed using a nested for loop. EndExample Code Live Demo#include using namespace std; void show(int n[4][3]); int main() {    int n[4][3] = {       {3, 4 ,2},       {9, 5 ,1},       {7, 6, 2},       {4, 8, 1}};    show(n);    return 0; } void show(int n[][3]) { cout

A dynamic 2D array is basically an array of pointers to arrays. Here is a diagram of a 2D array with dimenation 3 x 4.AlgorithmBegin    Declare dimension of the array.    Dynamic allocate 2D array a[][] using new.    Fill the array with the elements.    Print the array.    Clear the memory by deleting it. EndExample Code Live Demo#include using namespace std; int main() {    int B = 4;    int A = 5;    int** a = new int*[B];    for(int i = 0; i < B; ++i)       a[i] = new int[A];   ... Read More

In C++, it is faster to process a sorted array than an unsorted array due to some reasons related to algorithm efficiency and data access patterns. In this article, we see why this is the case and how sorting can improve performance of array processing. First of all, let see an example of processing time of a sorted and unsorted array. Processing Time: Sorted vs Unsorted Array In the example code below, we have used library of C++ STL to measure the time taken to process an unsorted array and a sorted array. The code counts how many ... Read More

Bit array is used to store true/false or yes/no type of values in very less memory. In this article, we will see how to create and use a bit array in C++. What is Bit Array? Bit array is a special array where each element can hold only 0 or 1. Instead of using a full byte (8 bits) for each boolean value, a bit array stores multiple values using just one bit each. Meaning, in a normal array of bool values, each value takes at least one byte. But in bit array, we store 8 values in one ... Read More

In this article, we will learn what is graph structured stack and how to implement it in a C++ program. What is Graph Structured Stack? Graph structured stack is a directed acyclic graph, where each directed path represents a stack. In this types of stack, the flow of execution is not linear like a traditional stack, instead the flow is represented using a graph structure. Each node in the graph can represent a function call or a state, and the edges define possible transitions or calls. This type of stacks are useful in advanced control flow handling like backtracking, ... Read More

DAG stands for Directed Acyclic Graph. It is a special type of graph where all edges are directed and there are no cyclic connections of edges. In this article, we will discuss how to check whether a graph is a DAG using Kahn’s algorithm (BFS based topological sorting). What is DAG? A DAG is a directed graph with no cycles. That means in this type graph it is not possible to start from any node and follow a sequence of edges such that you will return back to the starting node. DAGs are commonly used in applications like task ... Read More

Edge coloring is a method of coloring the edges of a graph, such that no two edges having a common vertex is colored with same color. A line Graph is a special type of graph which help us to assume an edge-coloring problem into a vertex-coloring problem. In other words, using a line graph makes edge coloring easier. In this article, we will discuss how to perform edge coloring of a graph using line graph and greedy coloring approach. What is Line Graph? Line graph is a special graph that is created from another graph. In the line ... Read More