C++ Tutorial index

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C++ Control Statements

C++ If C++ Nested if C++ If-else C++ If-else-if C++ Switch C++ Break C++ Continue C++ Goto C++ for loop C++ While loop C++ Do while loop

C++ functions

function in C++ C++ Call by Value C++ Call by Reference C++ Recursion function C++ inline function C++ Friend function C++ Friend functions function Pointer in C++ Sizeof() Operators in C++ C++ Math functions swap() function in C++ rand() and srand() in C / C++ wcscpy(), wcslen(), wcscmp() functions in C++ sort() function in C++ C++ vardiac() function System() function in C++ Fread function in C++ Programming Fscanf function in The C++ Gmtime function in C/C++ abs() function in C++ Sleep function in C++ Stoi function in C++ String erase() in C++ String Trim in C++ isprint() function in c++ is_trivial function in C++ div() function in C++ Set insert function in C++ rint(), rintf(), rintl() in C++ String append() function in C++ String push_back() in C++ String replace() in C++ Transform function in C++ exit() and _Exit() in C and C++ Std partition_point in C++ unique() in C++ ctime() function in C++ Gets() and Puts() in C++ Hypot(), hypotf() and hypotl() in C++ Log function in C++ Nearbyint() function in C++ setf() function in C++ Fill Function in C++ Map Find Function in C++ Malloc and Calloc in C++ Operator Function in C++ cin.get() in C++ seekp() Function in C++ eof() Function in C++ Emplace Back in C++ C++ macro function C_str in C++ Clock() in C/C++ round() function in C++ scalbn() function in C++ Stable Sort function in C++ Rotate in C++ Std:: Sort_heap in C++ Std::includes() in C++ STL std::memset() function in C++ Wcscmp() function in C++ Static Member function in C++ atof() function in C++ C++ Sin() function with Example cin.ignore() function in C++ Member function in C++ Pop_front Vector in C++ Vector resize() in C++ Malloc() and new in C++ std::distance in C++ C++ Date and Time fork() in C++ std::min in C++ isprint() in C++ rdbuf() in C++ fixed() Function in C++ setw() in C++ seekg() Function in C++ isdigit() Function in C++

C++ Function Miscellaneous

Precision of floating point numbers Using these functions floor(), ceil(), trunc(), round() and setprecision() in C++ function overloading in C++ Add two numbers using the function in C++ Advantage and disadvantage friend function C++ ATM machine program in C++ using functions Returning Multiple Values from a function using Tuple and Pair in C++ Find the Size of Array in C/C++ without using sizeof() function Pure Virtual function in C++ With Example Program Returning a function Pointer from a function in C/C++ Passing a Vector to a function in C++ functions in C++ With Types and Examples C++ Macro function Example Using Default Arguments with Virtual functions Virtual functions and Runtime Polymorphism Fesetround() and Fegetround() in C++ and their application Object as function Argument in C++ Private Member function in C++ Function Overriding in C++ C++ Program for Addition of Two Numbers Using functions function Object in C++ Elements of User Defined function in C++ Inline Functions in C++ Virtual Function in C++

C++ Arrays

Single dimension array Two dimension array

C++ Strings

C++ Strings

C++ Inheritance

C++ inheritance Single level inheritance Multilevel inheritance Multiple inheritance Hierarchical inheritance Hybrid inheritance

C++ Polymorphism

C++ Polymorphism C++ Overloading C++ Overriding C++ Virtual function

C++ Pointers

C++ Pointers C++ this pointer

C++ Exception Handling

C++ Exception Handling

C++ Constructors

C++ Constructors Default Constructor Parameterize Constructor Copy constructor Constructor Overloading Destructor

C++ File Handling

C++ File Handling C++ Writing to file C++ Reading file C++ Close file

C++ Programs

Structure of C++ Program Hello World Program in C++ C++ Program to Implement Shell Sort C++ Program to Implement Merge Sort C++ program to read string using cin.getline() C ++ Program: Alphabet Triangle and Number Triangle C++ Program: Matrix Multiplication C++ Program to Print Fibonacci Triangle C++ Program to find the product array puzzle C++ Program To Find Largest Subarray With 0 Sum C++ Program To Move All Zeros To The End of The Array C++ Program to find the element that occurs once C++ Program to find the largest number formed from an array Palindrome Number Program in C++ LCM Program in C++ Armstrong Number Program in C++ Factorial Program in C++ C++ Prime number program Program to convert infix to postfix expression in C++ Programs to Print Pyramid Patterns in C++ Array program in C++ Pattern programs in C++ Leap Year Program in C++ C++ Program for FCFS Depth First Search Program to Traverse a Graph in C++ inheritance Program in C++ Program that produces different results in C and C++ Example Program in C++ for input and Output Calculator Program using Switch in C++ Program for COPY Constructor in C++ Bank Program in C++ Anagram Program in C++

C++ Operators

Unary Operators in C++ Delete Operator in C++ C++ Bitwise XOR Operator Binary Operator Overloading in C++ Scope Resolution Operator in C++ C++ Ternary Operator New Operator in C++ Overloading array index operator in C++ Operator overloading in C++ Operators that cannot be overloaded in C++ Default Assignment Operator and References in C++ Conversion Operator in C++ Unary Operator Overloading in C++ Benefits of Operator Overloading in C++ Assignment Operator Overloading in C++ New and Delete Operator in C++ Insertion Operator in C++ Increment Operator in C++ Bitwise Operator in C++

C++ Examples

C++ Programming Examples While Loop Examples in C++ for Loop Examples in C++ Do-While Loop Examples in C++ SDL library in C++ with Examples C++ tcp client server example C++ tcp server example TCP Client Server Example in C++ Example of Parameterized Constructor in C++ Example of User Defined Data Type in C++

C++ Differences

C Vs C++ free() vs delete() in C++ Constructor Vs Destructor Passing by Reference Vs. Passing by the pointer in C++ C++ vs C# Structure Vs Class in C++ Virtual function Vs Pure Virtual function Structure Vs Class in C++ Exception Handling in C++ vs Java Static keyword in C++ vs Java inheritance in C++ vs Java C++ 11 vs C++ 14 vs C++ 17 Templates in C++ vs Generics in Java Bitwise Operator vs Logical Operator Type difference of Character literals in C VS C++ Copy Constructor vs Assignment Operator in C++ Map vs unordered_map in C++ Differences between #define & const in C/C++ Differences Between C Structures and C++ Structures Difference between Two Sets in C++ Difference between Exit and Return Differences between Local and Global Variable Difference between OOP and POP in C++ Difference between exit() and _Exit() in C++ Difference between int main() and int main(void) in C/C++ Difference Between Overloading and Overriding in C++ std::set_symmetric_difference in C++ Difference between Private and Protected in C++ Difference Between Encapsulation and Abstraction in C++ Difference between Template and Macro in C++ Difference between Abstraction and Interface in C++ Differences Between C++ and Javascript

How To

How to concatenate two strings in C++ How to Reverse a String in C++ using Do-While Loop How to Reverse a String in C++ using for Loop How to Reverse a String in C++ using While Loop How to create a table in C++ How to Setup Environment for C++ Programming on Mac How to call a void function in C++ How to create a directory or folder in C/C++ How to create a library in C++ How to create a stack in C++ How to create the Processes with fork in C++ How to Handle Divide by Zero Exception in C++ How to Declare Unordered Sets in C++ How to Sort an Array in C++ How to run program in turbo c++ How to Use Getline in C++ How is Multiset Implemented in C++ How to Build a Program in C++ How to Declare a 2d Array Dynamically in C++ How to create a button in C++ How the value is passed in C++ How to calculate size of string in C++ How to convert binary string to int in C++ How to convert string to float in C++ How to remove space from string in C++ How to use pair in C++ How to use the string find() in C++ How to Remove an Element From an Array in C++ How to Take Space Separated input in C++ How to Copy in Turbo C++ How to Use Pow in C++ How to Use Set in C++ How to Create Singleton Class in C++ How to Allocate Memory Dynamically in C++ How to Close Turbo C++ in Windows 10 How to Use Modulus in C++

C++ Questions

What does Buffer Flush mean in C++ What is endl in C++ What is Unary Operator Overloading in C++ Which operators cannot be overloaded in C++ What is Static Member function in C++ What is This Pointer in C++ What is Upcasting in C++ What Kind of Exceptions Are Available in C++ What is Memory Allocation for Objects in C++ What is a Linked List in C++ is assignment operator inherited in C++ When should we write own Assignment operator in C++ What is an Object in C++ What is Copy Constructor in C++ What is a Static Member Function in C++

C++ Interview Questions

Advanced C++ interview Questions Oops Interview Questions in C++

Miscellaneous

External merge sort in C++ Remove duplicates from sorted array in C++ C++ References C++ Mutable keyword initialize Array of objects with parameterized constructors in C++ Storage Classes in C goto statement in C and C++ C++ String Concatenation Heap Sort in C++ Swap numbers in C++ input Iterators in C++ Fibonacci Series in C++ Stack in C++ Maps in C++ Queue in C++ C++ Bitset C++ Algorithms Priority Queue in C++ C++ Multimap C++ Deque C++ array of Pointers Timsort Implementation Using C++ CPP Templates C++ Aggregation C++ Enumeration C++ Object Class C++ Queue initialize Vector in C++ Vector in C++ C++ STL Components C++ Maximum index Problem C++ find missing in the second array C++ Namespaces C++ OOPs Concept C++ Static C++ Structs C++ Try-Catch C++ User Defined Exceptions C++ Virtual Destructor Snake Code in C++ Splitting a string in C++ C++ Bidirectional Iterators C++ forward Iterators C++ Iterators C++ Output Iterators C++ Range-based for Loop Converting string into integer in C++ Type conversion in C++ Binary to Decimal in C++ Bit Manipulation in C++ C++ Constructor C++ Dijkstra Algorithm Using the Priority Queue C++ int into String C++ Signal Handling Decimal to Binary in C++ Decimal to Hexadecimal in C++ Decimal to Octal in C++ Hexadecimal to Decimal in C++ Octal to Decimal in C++ Reverse a Number in C++ C++ forward Iterators C++ Output Iterators Char Array to String in C++ Constructor Overloading in C++ Default arguments in C++ Different Ways to Compare Strings in C++ Dynamic Binding in C++ SET Data Structure in C++ Upcasting and Downcasting in C++ Reverse an Array in C++ Fast input and Output in C++ Copy elision in C++ Array of sets in C++ Binary Search in C++ Implementing the sets without C++ STL containers Smart pointers in C++ Types of polymorphism in C++ Const Keyword in C++ Type Casting in C++ Stringstream in C++ and its applications C++ Scope of Variables Star pattern in C++ using for Loops Top 5 IDEs for C++ That You Should Try Once Assertions in C/C++ C++ Convert int to String Continue in C++ While loop Diamond Pattern in C++ using for Loop infinite loop in C++ Loops in C++ Auto keyword in C++ C++ STL (Standard Template Library) Divide by Zero Exception in C++ Dynamic Constructor in C++ Dynamic Memory Allocation in C++ Floating Point Operations and Associativity in C, C++ and Java Implementation of a Falling Matrix in C++ Message Passing in C++ Pointer to Object in C++ Ways to Copy a Vector in C++ Structure Sorting (By Multiple Rules) in C++ Similarities between C++ and Java C++ Tricks for Competitive Programming Desired Capabilities in Selenium Web Driver in C++ Socket Programming in C++ Template Specialization in C++ Classes and Objects in C++ Convex hull Algorithm in C++ DES in C++ Structured Binding in C++ Functors in C++ Lambda Expression in C++ Roadmap to C++ Programming Substring in C++ Virtual base class in C++ Bits stdc++.h in C++ Top 14 Best Free C++ IDE (Editor & Compiler) for Windows in 2022 Bitmasking in C++ Features of OOPS in C++ Hospital Management Project in C++ include Guards in C++ Iostream in C++ Method overriding in C++ Naming Convention in C++ Nullptr in C++ Object Slicing in C++ Principles of Object-Oriented Programming in C++ Processing strings using std string stream in C++ Random Number Generator in C++ Singleton Design Pattern in C++ Size_t Data Type in C++ Skyline Problem in C++ Web Development in C++ Data Hiding in C++ Hashing in C++ Object in C++ Sum of all Elements between k1’th and k2’th Smallest Elements Virtual class in C++ Vector Size in C++ Top best IDEs for C/C++ Developers in 2022 Tensorflow in C++ Sliding Window Technique in C++ Reverse String Word-Wise in C++ RTTI in C++ Pthreads or POSIX Threads in C++ Reserved Keywords in C++ 10 Best C and C++ Books for Beginners & Advanced Programmers Add two numbers represented by two arrays in C++ Array of Object in C++ Containership in C++ Counting Frequencies of Array Elements in C++ Decltype type Specifier in C++ Dynamic _Cast in C++ Features and Use of Pointers in C/C++ int Max and int Min in C/C++ is It Fine to Write Void Main Or Main in C/C++ Compile Time Polymorphism in C++ Division in C++ Factorial of a Number in C++ using while Loop Multiset in C++ 4 Pillars of OOPs Approach in C++ Backtracking Time Complexity in C++ C++ Global Variable C++ Pipe Tutorial Observer Design Pattern in C++ Private inheritance in C++ Pthread in C++ Parameters Pointers in C++ Abstract Factory Design Pattern in C++ Ascending order in C++ Call by Pointer in C++ Constexpr in C++ Deadlock in C++ Design Patterns in C++ Factory Method for Designing Pattern in C++ Name Mangling and extern in C++ Preventing Object Copy in C++ Quick Sort in C++ Single Handling in C++ Use of inheritance in C++ User-defined literals in C++ Vector methods in C++ Void * in C and C++ Zombie and Orphan Process in C++ List and Vector in C++ List iterators in C++ Merging Two Vectors in C++ Early Binding and Late Binding in C++ Factory Design Pattern in C++ Fisher-Yates shuffle algorithm in C++ for Auto in C++ Group anagrams in C++ Dynamic Casting in C++ 2D Vector initialization in C++ C++ GUI Visual Studio C++ IPC C++ Permutation Overloading Stream insertion in C++ Array sum in C++ STL C++ Define Macro C++ Design C++ Factory Pattern Convert String to Uppercase in C++ initializer list in C++ Iterator invalidation in C++ Lower bound in C++ Modulus of Two float numbers or double number Pass by value in C++ Stack size in C++ Unordered_map in C++ Binary String to int C++ Boost C++ Exception handling in constructor and destructor in C++ Explain class template in C++ Kadane Algorithm in C++ Map of Pairs in STL Pair in C++ Access Specifiers in C++ Add Two Numbers in C++ Using Class C++ Socket Programming Windows Cube root in C++ C++ Protected inheritance C++ Return Object Static Data Members in C++ Association in C++ Boost libraries in C++ Automatic Storage Class in C++ C++ Move Constructor Cast in C++ C++ 11 Lambda C++ Multithreading Bottom-up Approach in C++ C++ Static Class C++ Static Member C++ Static Variable C++ Template Class Implementation Kruskals Algorithm in C++ Kth Permutation Sequence in C++ Kth Smallest Element Using Priority Queue in C++ Min Heap in C++ Multilevel inheritance in C++ Playfair Cipher Algorithm in C++ Exception Handling in Java and C++ Sorting in C++ Time and Space Complexity for Loops in C++ Convert Vector To String in C++ Cascading in C++ Control Structure in C++ Passing Object as argument in C++ Vector Pair in C++ String Data Types in C++ Topological Sort in C++ C++ Move Semantics C++ Static Library Linking Call by Value and Call by Reference in C++ Data Structures algorithms and application in C++ Dereferencing a Pointer in C++ Linked List in C++ All Swing Components in C++ anonymous Object in C++ Cerr in C++ Control Flow Statement in C++ cstdlib in C++ Exception Objects in C++ Base Class and Derived Class in C++ Creating A Menu in C++ Escape Sequence in C++ Explicit in C++ int range 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in C++ Insert Function in C++ Metaclass in C++ Move Constructor in C++ Move Semantics in C++

Factorial Program in C++

C++ Factorial Program:

The product of all positive descending integers is the factorial of n. n! denotes the factorial of n. For instance:

5! = 5*4*3*2*1=120
4! = 4*3*2*1=24

In Combinations and Permutations, the factorial is commonly utilized (mathematics). The factorial program may be written in a variety of ways in C++. Let's look at the three different approaches to create a factorial program.

  • Looping Factorial Program
  • Recursive factorial program

Looping Factorial Program in C++:

#include <iostream> 
#include <stdlib>
#include <bits/stdc++.h> 
using namespace std;  
int main()  
{  
   int i,factorial=1,number;    
  cout<<"enter any Number: ";    
 cin>>number;    
  for(i=1;i<=number;i++){    
  factorial=factorial*i;    
  }    
  cout<<"Factorial of " <<number<<" is: "<<fact<<endl;  
  return 0;  
}  

OUTPUT:

Enter any Number: 4  
Factorial of 4 is:  24
………………………………
Process executed in 1.212 seconds
Press any key continue.

Explanation

In the above program in C++, we are iterating in for loop and signing factorial multiply by the number itself.

Let's look at a recursive factorial program in C++.

#include<iostream> 
#include<bits/stdc++.h>
#include<stdlib>   
using namespace std;      
int main()    
{    
int factorial(int);    
int fact,value;    
cout<<"enter any number: ";    
cin>>value;    
fact=factorial(value);    
cout<<"Factorial of a number is: "<<fact<<endl;    
return 0;    
}    
int factorial(int i)    
{    
if(i<0)    
return(-1); /*Wrong value*/      
if(i==0)    
return(1);  /*Terminating condition*/    
else    
{    
return(i*factorial(i-1));        
}    
}  

OUTPUT:

Enter any number: 8
Factorial of a number is: 40320
……………………………………………….
Process executed in 1.11 seconds
Press any key to continue.

Explanation

In the above program in C++, we have used a recursive version to find the factorial of the given number. In the return statement we are making call to factorial function recursively.

Using while loop for finding the factorial of a number in C++:

// C++ program for factorial of a number
#include <iostream>
#include <bits/stdc++.h>
#include <stdlib>
using namespace std; 
// function to find factorial of given
// number using while loop
unsigned int factorial(unsigned int a)
{
	if(a == 0)
		return 1;
	int x = a, fact = 1;
	while (a / x != a) {
		fact = fact * x;
		x--;
	}
	return fact;
}
// Driver code
int main()
{
	int num = 5;
	cout << "Factorial of "
		<< num << " is "
		<< factorial(num) << endl;
	return 0;
}

OUTPUT:

Factorial of 8 is 40302
………………………………...
Process Executed in 0.1212 seconds
Press nay key to continue.

Explanation

In the above program in C++, we are using loops for finding out the factorial. In the line number eleven we are using while loop for finding out the factorial.

Let us see the factorial of a large number in C++:

// C++ program to compute factorial of big numbers
#include<iostream>
#include<bits/sdtc++.h>
#include<stdlib>
using namespace std; 
// Maximum number of digits in output
#define MAX 500


int multiply(int a, int res[], int res_size); 
// This function finds factorial of large numbers
// and prints them
void factorial(int n)
{
	int res[MAX]; 
	// Initialize result
	res[0] = 1;
	int res_size = 1; 
	// Apply simple factorial formula n! = 1 * 2 * 3 * 4...*n
	for (int a=2; a<=n; a++)
		res_size = multiply(a, res, res_size); 
	cout << "Factorial of given number is \n";
	for (int b=res_size-1; b>=0; b--)
		cout << res[b];
}
// This function multiplies x with the number
// represented by res[].
// res_size is size of res[] or number of digits in the
// number represented by res[]. This function uses simple
// school mathematics for multiplication.
// This function may value of res_size and returns the
// new value of res_size
int multiply(int a, int res[], int res_size)
{
	int carry = 0; // Initialize carry
	// One by one multiply n with individual digits of res[]
	for (int b=0; b<res_size; b++)
	{
		int prod = res[b] * a + carry; 
		// Store last digit of 'prod' in res[]
		res[b] = prod % 10; 
		// Put rest in carry
		carry = prod/10;
	}
	// Put carry in res and increase result size
	while (carry)
	{
		res[res_size] = carry%10;
		carry = carry/10;
		res_size++;
	}
	return res_size;
}
// Driver program
int main()
{
	factorial(200);
	return 0;
}

OUTPUT:

Factorial of given number is
788657867364790503552363213932185062295135977687173263294742533244359449963403342920304284011984623904177212138919638830257642790242637105061926624952829931113462857270763317237396988943922445621451664240254033291864131227428294853277524242407573903240321257405579568660226031904170324062351700858796178922222789623703897374720000000000000000000000000000000000000000000000000
--------------------------------
Process exited after 0.07152 seconds with return value 0
Press any key to continue . . 

Explanation

In the above program in C++, factorial function takes n as parameter in that we are applying simple factorial formula and in the multiply function what we doing is One by one multiplying n with individual digits of res [].

Let us see another method of linked list to find the factorial:

#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for (int i = a; i <= b; i++)
using namespace std;
class Node {
public:
	int data;
	Node* prev;
	Node(int n)
	{
		data = n;
		prev = NULL;
	}
};
void Multiply(Node* tail, int n)
{
	Node *temp = tail,
		*prevNode = tail; // Temp variable for keeping tail
	int carry = 0;
	while (temp != NULL) {
		int data = temp->data * n + carry;
		temp->data = data % 10; // stores the last digit
		carry = data / 10;
		prevNode = temp;
		temp = temp->prev; // Moving temp by 1 prevNode will
						// now denote temp
	}
	// If carry is greater than 0 then we create another
	// node for it.
	while (carry != 0) {
		prevNode->prev = new Node((int)(carry % 10));
		carry /= 10;
		prevNode = prevNode->prev;
	}
}
void print(Node* tail)
{
	if (tail == NULL) // Using tail recursion
		return;
	print(tail->prev);
	cout
		<< tail->data; // Print linked list in reverse order
}
// Driver code
int main()
{
	int n = 20;
	Node tail(1); // Create a node and initialise it by 1
	rep(i, 2, n)
		Multiply(&tail, i); // Run a loop from 2 to n and
							// multiply with tail's i
	print(&tail); // Print the linked list
	cout << endl;
	return 0;
}

OUTPUT:

243290200817123640000

Explanation

In the above program in C++, we have used linked list and in the multiply function we are taking tail node pointer and size n to calculate the factorial and after that printing it back to the console.