Basic Arithmetic & Input/Output¶

Mastering how to handle variables and perform calculations is the first step in any programming language. These problems are language-agnostic and can be solved in C, C++, Java, Python, or any other language.

1. The Classic "Hello World"¶

Rating: Newbie | Difficulty: Easy Print "Hello, World!" to the screen.

💡 Hint

Use your language's standard output function (e.g., printf in C, cout in C++, System.out.println in Java).

2. Sum of Two Numbers¶

Rating: Newbie | Difficulty: Easy Take two integers as input from the user and print their sum.

💡 Hint

Declare two variables, use an input function (e.g., scanf or Scanner), and print a + b.

3. Temperature Converter (Celsius to Fahrenheit)¶

Rating: Newbie | Difficulty: Easy Input temperature in Celsius and convert it to Fahrenheit using the formula: F = (C * 9/5) + 32.

💡 Hint

Use `float` or `double` for precision since division is involved.

4. Area of a Circle¶

Rating: Beginner | Difficulty: Easy Input the radius of a circle and calculate its area (πr²). Use 3.14159 for π.

💡 Hint

Area = 3.14159 * radius * radius.

5. Simple Interest Calculator¶

Rating: Beginner | Difficulty: Easy Calculate Simple Interest based on input: Principal, Rate, and Time. Formula: SI = (P * R * T) / 100.

💡 Hint

Input three variables and apply the formula directly.

6. Swap Two Numbers (With Third Variable)¶

Rating: Beginner | Difficulty: Easy Input two numbers and swap their values using a temporary third variable.

💡 Hint

temp = a; a = b; b = temp;

7. Swap Two Numbers (Without Third Variable)¶

Rating: Intermediate | Difficulty: Medium Swap two numbers without using any extra variables.

💡 Hint

Use addition and subtraction: a = a + b; b = a - b; a = a - b;

8. Time Converter¶

Rating: Intermediate | Difficulty: Medium Input total seconds and convert it into Hours : Minutes : Seconds format.

💡 Hint

Use the modulus operator %. Hours = seconds / 3600, remaining seconds =

seconds
% 3600

.

9. Body Mass Index (BMI)¶

Rating: Intermediate | Difficulty: Medium Calculate BMI using weight (kg) and height (meters). Formula: BMI = weight / (height * height).

💡 Hint

Ensure height is taken as a float/double.

10. ASCII Value Finder¶

Rating: Beginner | Difficulty: Easy Input a character and print its corresponding ASCII integer value.

💡 Hint

In C/C++/Java, you can simply cast a char to an int.

11. Days to Years, Weeks, and Days¶

Rating: Intermediate | Difficulty: Medium Convert a given number of days into Years, Weeks, and remaining Days. (Assume 1 Year = 365 Days).

💡 Hint

Years = `days / 365`. Remaining days = `days % 365`.

12. Compound Interest¶

Rating: Advanced | Difficulty: Medium Calculate Compound Interest. Formula: A = P(1 + r/n)^{nt}.

💡 Hint

You will need a math library for the power function (e.g., pow() in C/C++, Math.pow() in Java).

13. Distance Between Two Points¶

Rating: Advanced | Difficulty: Medium Input coordinates (x1, y1) and (x2, y2) and find the distance between them. Formula: √((x2-x1)² + (y2-y1)²).

💡 Hint

Use sqrt() and pow() functions from your language's math library.

14. Total and Percentage¶

Rating: Beginner | Difficulty: Easy Input marks of 5 subjects (out of 100 each). Calculate the Total and the Percentage.

💡 Hint

Percentage = (Total / 500.0) * 100.

15. Volume of a Cylinder¶

Rating: Pro | Difficulty: Medium Input radius and height of a cylinder. Calculate the volume. Formula: V = πr²h.

💡 Hint

Volume = 3.14159 * radius * radius * height.

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