C++ Tutorial index

C++ Tutorial C++ History C++ installation C++ First Program C++ cin and cout C++ Data type C++ Variable C++ operator C++ Keywords C++ OOPS Concepts C++ Comments C++ Data Abstraction C++ Identifier C++ Memory Management C++ Storage Classes C++ Void Pointer C++ Array to function C++ Expressions C++ Features C++ Interfaces C++ Encapsulation

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 in C++ Maximum Value in Vector in C++ NPTEL Programming in C++ Shared Pointer in C++ Static Member Function in C++ With Example The Diamond Pattern in C++ Const ptr C++ Const_Cast C++ Area Of Triangle in C++ Array input in C++ Cin String in C++ Coroutine in C++ Gui Design in C++ integer in C++ Advantages and Disadvantages of inheritance in C++ C++ IDE Linux C++ Mini Project With Source Code And Output C++ Variables Types Containers in C++ Dynamic Binding in C++ Explain Access Specifiers in C++ Iomanip in C++ Noexcept in C++ C++ Reference Initializer in C++ Constant Arguments in C++ Vector in C++ Stl Singleton Pattern in C++ Error Handling in C++ C++ Thread Id to Int C Str in C++ C++ Shared Ptr Scope Resolution Operator in C++ C++ Random Number Between 1 and 10 File Opening Mode in C++ New and Delete in C++ Big Integers in C++ Stack Unwinding in C++ C++ Syntax Link Map cbegin() and cend() function in C++ STL Hamming Code Implementation in C++ Files and Streams in C++ Private Destructor in C++ Semaphore in C++ Map Emplace_hint() function in C++ STL Complex Number Program in C++ Meta Classes in C++ C++ Delegates Custom Sort in C++ RAII in C++ Babylonian Square Root Algorithm in C++ File Input and output operation in C++ Sum of Digits of a Number in C++ C++ Type Traits Binary Search Tree Program in C++ Tree in C++ Built in Types in C++ Catch all Exceptions in C++ C++ Template Class Declaration and Definition C++ Generic Programming Introduction Fundamental Data Types in C++ API in C++ Menu Driven Program in C++ Exception Specification in C++ Bit Manipulation in C++ Dynamic Initialization Of Objects in C++ Returning Object from a Function in C++ Class and Structure in C++ Edmonds Karp Algorithm in C++ Flush in C++ Find Substring in C++ Input and Output Operators in C++ Final in C++ Lvalue and Rvalue in C++ C++ Singleton File Stream in C++ Has a Relationship in C++ Character Set in C++ Menu Driven Program in C++ Final Keyword in C++ Associative Containers in C++ Decltype in C++ Insert Function in C++ Metaclass in C++ Move Constructor in C++ Move Semantics in C++

Different Ways to Compare Strings in C++

This section will go over the many methods for comparing strings in the C++ programming language. The string comparison checks if the first string is equal to another string. HELLO and Hello are two distinct strings.

In the C++ programming language, there are several techniques to compare strings, as follows:

  • strcmp ( ) is a function that can be used to compare two strings.
  • Using the method compare ( )
  • Relational Operators in Use
  • Using the for loop and the If condition
  • Using a custom function

strcmp ( ) function

The strcmp ( ) method is a string.h header file pre-defined library function. The strcmp () method lexicographically compares two strings. This indicates that the strcmp ( ) method compares the first and second strings character by character until both strings are identical or a NULL character is found.

Following is the syntax:

int strcmp ( const char *leftstr, const char *rightstr );   
  • The letters of the right string are defined by leftstr.
  • The characters of the right-wing unit are defined by rightstr.

Let's use the strcmp() function in C++ to build a programme that compares strings:

#include < iostream >  
#include < bits/stdc++.h >
#include < stdlib >
using namespace std ;  
#include < string.h >  
int main ( )  
{  
    // declare strings  
    const char * str1 = " This is Tutorial And Example" ;  
    const char * str2 = " This is Tutorial And Example " ;  
    const char * str3 = " Tutorial And Example " ;  
    const char * str4 = " Tutorial And Example " ;  
    cout << " String 1: " << str1 << endl ;  
    cout << " String 2: " << str2 << endl ;  
    // use strcmp ( ) function to validate the strings are equal  
    if ( strcmp ( str1 , str2 ) == 0 )  
    {  
        cout << " \n Both strings are equal. " << endl ;  
    }  
    else   
        {      
        cout << " The strings are not equal. " << endl ;  
    }  
    cout << " \n String 3: " << str3 << endl ;  
    cout << " String 4: " << str4 << endl ;  
    // use strcmp ( ) function to validate the strings are equal  
    if ( strcmp ( str3 , str4 ) == 0 )  
    {  
        cout << " \n Both strings are equal. " << endl ;  
    }     
    else   
        cout << " \n The strings are not equal. " ;      
return 0 ;  
}  

OUTPUT:

String 1: This is Tutorial And Example
String 2:  This is Tutorial And Example
Both strings are equal. 
String 3:  Tutorial And Example
String 4:  Tutorial And Example
The strings are not equal.

Explanation:

From the left side to the end of both strings, the leftstr string compares each character with the second string. The strcmp () method returns equal strings when the strings are equal. Otherwise, the wires will not fit.

compare ( ) function

The C++ language's compare ( ) function is a pre-defined library function. Based on the matching cases, the compare ( ) method compares two strings.

Following is the syntax:

int compare ( const string &str ) const ;   

Let's make simple software that uses the C++ compare ( ) function to compare two strings:

#include < iostream >  
#include < bits/stdc++.h >
#include < stdlib >
using namespace std ;  
int main ( )  
{  
    string str1 , str2 ; // declare string variable  
    cout << " enter the string 1: " ;   
    cin >> str1 ;   
    cout << " enter the string 2: " ;  
    cin >> str2 ;   
    // use compare ( ) function to compare the second string with first string  
    int i = str1 . compare ( str2 ) ;  
    if ( i < 0 )  
    {  
        cout << str1 << " is smaller than " << str2 << " string" << endl ;  
    }  
    else if ( i > 0 )  
    {  
        cout << str2 << " is greater than " << str1 << " string." << endl ;  
    }  
    else // i == 0 ;  
    {  
        cout << " Both strings are equal." ;  
    }  
return 0 ;  
}

OUTPUT:

1st Run:
Enter the string 1: Tutorial And Example
Enter the string 2: Tutorial And Example
Program is smaller than program string
2nd Run:
Enter the string 1: JAVATPOINT
Enter the string 2: JAVATPOINT
Both strings are equal.  

Explanation:

  • The method returns 0 if two strings are the same
  • If the first string's character value is less than the second string's, the method returns 0.
  • The method returns more than 0 or >0 if the second string is longer than the first.

Relation Operator

In C++, it's the operator for comparing two textual or numerical values. Relational operators in C++ include the ' == ', ' != ',  >, and operators. However, to compare the text quickly, we just require two operators: ' == ' equal to and ' != ' not equal to a relational operator.

Following is the syntax:

String1 == string2  // In this case, we'll use the double equal to operator.
Or   
String1 != string2 // We utilize the not equal to operator in this case.

NOTE:

In C++, the Equal to (==) operator is used to compare two strings.

Let's make a C++ program that compares strings with the equal to (==) operator./co

#include < iostream >  
#include < bits/stdc++.h >
#include < stdlib >
using namespace std ;  
int main ( )  
{  
    // declare string variables  
    string str1 ;  
    string str2 ;  
    cout << " enter the String 1: " << endl ;   
    cin >> str1 ;  
    cout << " enter the String 2: " << endl ;  
    cin >> str2 ;  
      
    // use ' == ' equal to operator to check the equality of the string  
    if ( str1 == str2 )  
    {  
        cout << " String is equal." << endl ;  
    }  
    else  
    {  
        cout << " String is not equal." << endl ;  
    }  
    return 0 ;  
}  

OUTPUT:

Enter the String 1:
Tutorial And Example
 Enter the String 2:
Tutorial And Example
String is not equal.
2nd Execution: 
Enter the String 1:
This is Tutorial And Example
Enter the String 2:
This is Tutorial And Example
String is equal.

Explanation:

In the above program in C++ we shown the use of == operator. We are checking if the str1 and str2 is equal and if they are equal then print that string are equal.

NOTE:

The Not Equal To ( != ) Relational Operator is used to compare two strings.

Let's use the Not Equal To ( != ) operator in C++ to develop a program that compares whether the strings are equal or not.

#include < iostream >  
#include < bits/stdc++.h >
#include < stdlib >
using namespace std ;  
int main ( )  
{  
    // declare string variables  
    string str1 ;  
    string str2 ;  
    cout << " enter the String 1: " << endl ;  
    cin >> str1 ;  
    cout << " enter the String 2: " << endl ;  
    cin >> str2 ;  
    // use ' != ' not equal to operator to check the equality of the string  
    if ( str1 != str2 )  
    {  
        cout << " String is not equal." << endl ;  
    }  
    else  
    {  
        cout << " String is equal." << endl ;  
    }  
    return 0 ;  
}  

OUTPUT:

Enter the String 1:
This is Tutorial And Example
 Enter the String 2:
This is Tutorial And Example
 String is not equal.
2nd Run: 
Enter the String 1:
Hey
 Enter the String 2:
Hey
 String is equal.

Explanation:

In the above example of a program in C++, we have shown the use of != operator. We are checking if str1 is not equal to str2 and if this statement is true then doing the printing part.

In C++, use for loop and if statement to compare two strings:

Let's use for loop and if statement in C++ to develop a program that compares whether the strings are equal or not:

#include < iostream >  
using namespace std ;  
int main ( )  
{  
    char s1 [ 50 ] , s2 [ 50 ] ; // declare character array  
    int i, disp;  
    cout << " enter the String 1: " << endl;  
    cin >> s1;  
    cout << " enter the String 2: " << endl;  
    cin >> s2;  
    for (i = 0; s1[i] == s2[i] && s1[i] == '\0'; i++);  
    if (s1[i] < s2[i])  
    {  
        cout << " String 1 is less than String 2";  
    }  
    else if (s1[i] > s2[i])  
    {  
        cout << " String 2 is less than String 1";  
    }  
    else  
    {  
        cout << " String 1 is equal to String 2";  
    }  
    return 0;  
 }  

OUTPUT:

Enter the String 1:
MOST WELCOME!
Enter the String 2:
MOST WELCOME!
String 1 is equal to String 2

Explanation:

In the above example of a program in C++,we declare a character string and with the help of for loop we are checking if string 1 is equal to string 2.

In C++, use the User-defined function to compare two strings

Let's utilize the user-defined function in C++ to make a simple program that compares the first string to another string.

#include <iostream>  
using namespace std;  
void RelationalCompare ( string str1, string str2)  
{  
    // use relational not equal operator  
    if ( str1 != str2)  
    {  
        cout << str1 << " is not equal to " << str2 << " string. " << endl;  
        if (str1 > str2)  
        {  
            cout << str1 << " is greater than " << str2 << " string." << endl;  
        }  
        else  
        {  
            cout << str2 << " is greater than " << str1 << " string." << endl;      
        }  
    }  
        else  
            cout << str1 << " is equal to " << str2 << " string." << endl;  
}  
int main ()  
{  
    string str1 ( "Tutorial");  
    string str2 ( "And Example");  
    // call function  
    RelationalCompare (str1, str2);  
    string str3 ("Tutorial And Example");  
    string str4 ("Tutorial And Example");  
    RelationalCompare (str3, str4);  
    return 0;  
}  

OUTPUT:

Tutorial is not equal to And Examples string.
And Example is greater than Tutorial string.
Tutorial And Example is equal Tutorial And Example to string.

Explanation:

In the above example of a program in C++, we have shown the use of user define function to compare two string. We have created a function called RelationalCompare which takes two string as a parameter and perform its function recursively.