#include <iostream>

using namespace std;

 main() {
    const int studentID = 'BC23041663' ;
    const string studentName = "khadeeja bibi";

    cout << "Hello " << studentName << ", Student ID=BC" << studentID << " Welcome to the Main Menu\n";

    int choice;
    float num, result = 0;
    char cont;

    do {
        cout << "\n1. Addition\n";
        cout << "2. Subtraction\n";
        cout << "3. Multiplication\n";
        cout << "4. Division\n";
        cout << "5. Exit\n";
        cout << "Enter your choice: ";
        cin >> choice;

        switch(choice) {
            case 1:
                cout << "\nHow many numbers do you want to add? ";
                int n_add;
                cin >> n_add;
                result = 0;
                for(int i = 0; i < n_add; i++) {
                    cout << "Enter number " << i + 1 << ": ";
                    cin >> num;
                    result += num;
                }
                cout << "Result of addition: " << result << endl;
                break;
            case 2:
                cout << "\nHow many numbers do you want to subtract? ";
                int n_sub;
                cin >> n_sub;
                cout << "Enter number 1: ";
                cin >> result;
                for(int i = 0; i < n_sub - 1; i++) {
                    cout << "Enter number " << i + 2 << ": ";
                    cin >> num;
                    result -= num;
                }
                cout << "Result of subtraction: " << result << endl;
                break;
            case 3:
                cout << "\nHow many numbers do you want to multiply? ";
                int n_mul;
                cin >> n_mul;
                result = 1;
                for(int i = 0; i < n_mul; i++) {
                    cout << "Enter number " << i + 1 << ": ";
                    cin >> num;
                    result *= num;
                }
                cout << "Result of multiplication: " << result << endl;
                break;
            case 4:
                cout << "\nHow many numbers do you want to divide? ";
                int n_div;
                cin >> n_div;
                cout << "Enter number 1: ";
                cin >> result;
                for(int i = 0; i < n_div - 1; i++) {
                    cout << "Enter number " << i + 2 << ": ";
                    cin >> num;
                    if(num == 0) {
                        cout << "Error! Division by zero is not allowed." << endl;
                        break;
                    }
                    result /= num;
                }
                cout << "Result of division: " << result << endl;
                break;
            case 5:
                cout << "\nExiting program. Goodbye!\n";
                break;
            default:
                cout << "\nInvalid choice. Please try again.\n";
        }
        if (choice != 5) {
            cout << "\nDo you want to continue? (y/n): ";
            cin >> cont;
        }
    } while(choice != 5 && (cont == 'y' || cont == 'Y'));

    return 0;
}
by

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}