Assignment: Variables and Data Types - Basics of C++ - Software Development

Instructions 

Answer the following questions by selecting the correct option or filling in the blanks with the appropriate answers. For hands-on questions, write the code snippets to fulfill the given requirements

Multiple Choice Questions (MCQs)

Q.1. Which of the following is NOT a valid C++ data type?
(a) float
(b) string
(c) double
(d) char

Ans. (b)

Q.2. What is the size of the "int" data type in C++?
(a) 4 bytes
(b) 2 bytes
(c) 8 bytes
(d) It varies depending on the system

Ans. (d)

Q.3. Which of the following is the correct way to declare a variable in C++?
(a) var x;
(b) x = 5;
(c) int x;
(d) 5 = x;

Ans. (c)

Q.4. What is the value of the variable "result" after executing the following code snippet?
int num1 = 10;
int num2 = 3;
double result = num1 / num2;
(a) 3.0
(b) 3
(c) 3.3333
(d) Compilation error

Ans. (b)

Q.5. Which operator is used to find the remainder of a division operation in C++?
(a) /
(b) %
(c) *
(d) $

Ans. (b)

Higher Order Thinking Questions (HOTS)

Q.1. Write the correct C++ code to swap the values of two variables, x and y, without using a temporary variable.

int x = 5;

int y = 10;

x = x + y;

y = x - y;

x = x - y;

Q.2. Explain the difference between declaring a variable and initializing a variable.

Declaring a variable means creating its name and specifying the data type, while initializing a variable means assigning a value to it.

Q.3. What are the basic differences between the "float" and "double" data types in C++?

The "float" data type in C++ is a single-precision floating-point type that occupies 4 bytes of memory, while the "double" data type is a double-precision floating-point type that occupies 8 bytes of memory. The "double" data type can represent larger and more precise decimal numbers compared to "float."

Q.4. Write a C++ code snippet to calculate the area of a circle, given the radius as input from the user.

#include <iostream>

using namespace std;

int main() {

    double radius;

    double area;

    const double pi = 3.14159;

    cout << "Enter the radius of the circle: ";

    cin >> radius;

    area = pi * radius * radius;

    cout << "The area of the circle is: " << area << endl;

    return 0;

}

Q.5. How can you convert an integer variable to a string in C++? Provide an example.

#include <iostream>

#include <string>

using namespace std;

int main() {

    int num = 12345;

    string str = to_string(num);

    cout << "The converted string is: " << str << endl;

    return 0;

}

Fill in the Blanks

Q.1. The process of reserving memory space for a variable is called __________.

Ans. Allocation

Q.2. The _________ data type in C++ is used to store single characters.

Ans. char

Q.3. The _________ operator is used to access the memory address of a variable.

Ans. & (ampersand)

Q.4. The __________ function in C++ is used to read input from the user.

Ans. cin

Q.5. A variable that can hold the address of another variable is called a ________ variable.

Ans. pointer

True or False

Q.1. In C++, the variable names are case-insensitive.

Ans. False

Q.2. The "cin" statement is used to output data in C++.

Ans. False

Q.3. A character variable can store multiple characters.

Ans. False

Q.4. The "sizeof" operator returns the size of a variable in bytes.

Ans. True

Q.5. All variables in C++ must be declared before they can be used.

Ans. True

Hands-On Questions

Q.1. Write a C++ program that declares two integer variables, x and y, and assign values of your choice to them. Print their sum.

#include <iostream>

using namespace std;

int main() {

    int x = 5;

    int y = 10;

    int sum = x + y;

    cout << "The sum of x and y is: " << sum << endl;

    return 0;

}

Q.2. Write a C++ program that calculates and prints the average of three floating-point numbers input by the user.

#include <iostream>

using namespace std;

int main() {

    float num1, num2, num3;

    float average;

    cout << "Enter three numbers: ";

    cin >> num1 >> num2 >> num3;

    average = (num1 + num2 + num3) / 3;

    cout << "The average is: " << average << endl;

    return 0;

}

Q.3. Write a C++ program that prompts the user to enter their name and age. Then, print a message that says "Hello, <name>! You are <age> years old."

#include <iostream>

#include <string>

using namespace std;

int main() {

    string name;

    int age;

    cout << "Enter your name: ";

    cin >> name;

    cout << "Enter your age: ";

    cin >> age;

    cout << "Hello, " << name << "! You are " << age << " years old." << endl;

    return 0;

}

Q.4. Write a C++ program that takes a temperature value in Celsius and converts it to Fahrenheit. The formula to convert Celsius to Fahrenheit is: F = (C * 9/5) + 32.

#include <iostream>

using namespace std;

int main() {

    double celsius, fahrenheit;

    cout << "Enter temperature in Celsius: ";

    cin >> celsius;

    fahrenheit = (celsius * 9 / 5) + 32;

    cout << "Temperature in Fahrenheit: " << fahrenheit << endl;

    return 0;

}

Q.5. Write a C++ program that calculates and prints the factorial of a number entered by the user. The factorial of a non-negative integer n is denoted by n!, and it is the product of all positive integers less than or equal to n.

#include <iostream>

using namespace std;

int main() {

    int number;

    int factorial = 1;

    cout << "Enter a number: ";

    cin >> number;

    for (int i = 1; i <= number; i++) {

        factorial *= i;

    }

    cout << "The factorial of " << number << " is: " << factorial << endl;

    return 0;

}