Write a Program of if else switch case and loops in C++

Write a Program to Implement Control Structures (if-else, switch-case, loops) in C++

Control structures in C++ are essential for managing the flow of a program. They help in making decisions and repeating tasks based on conditions. In this blog, we will cover three major control structures: if-else, switch-case, and loops (like for, while, and do-while), along with a practical example in C++.

Mastering these structures is fundamental for writing logical, structured, and dynamic code in C++.

🔹 Types of Control Structures

1. Conditional Statements

if-else**: Executes a block of code if a condition is true, otherwise executes another block.

2. Switch-Case

Allows selection among multiple code blocks based on a variable’s value.

3. Loops

• for: Executes a block of code a fixed number of times.
• while: Executes as long as a condition is true.
• do-while: Similar to while, but ensures at least one execution.

✅ C++ Program to Demonstrate All Control Structures

#include <iostream>

using namespace std;

int main() {

    int choice, number;

    // if-else statement

    cout << "Enter a number: ";

    cin >> number;

    if (number % 2 == 0)

        cout << "The number is even." << endl;

    else

        cout << "The number is odd." << endl;

    // switch-case statement

    cout << "\nMenu:\n1. Square\n2. Cube\nEnter your choice (1 or 2): ";

    cin >> choice;

    switch (choice) {

        case 1:

            cout << "Square of " << number << " is " << number * number << endl;

            break;

        case 2:

            cout << "Cube of " << number << " is " << number * number * number << endl;

            break;

        default:

            cout << "Invalid choice!" << endl;

    }

    // for loop

    cout << "\nFirst 5 multiples of " << number << ": ";

    for (int i = 1; i <= 5; i++) {

        cout << number * i << " ";

    }

    // while loop

    cout << "\n\nCountdown from 5 using while loop: ";

    int count = 5;

    while (count > 0) {

        cout << count << " ";

        count--;

    }

    // do-while loop

    cout << "\n\nPrint number at least once using do-while loop: ";

    int x = 0;

    do {

        cout << x << " ";

        x++;

    } while (x < 1);

    return 0;

}

🔍 Output Explanation

Suppose the user enters `4`:

The number is even.

Menu:

1. Square

2. Cube

Enter your choice: 2

Cube of 4 is 64

First 5 multiples of 4: 4 8 12 16 20 

Countdown from 5 using while loop: 5 4 3 2 1 

Print number at least once using do-while loop: 0