Ask Programiz - Human Support for Coding Beginners

Hi there! Multiplying numbers in Python is quite straightforward, and it's great that you're diving into this lesson on data types.

To perform multiplication, you'll use the asterisk symbol (*), which serves as the multiplication operator in most programming languages, including Python.

Let's update the code you're working with to perform an actual multiplication:

result = 2 * 2
print("2 * 2 =", result)

This code assigns the result of 2 * 2 to the variable result and then prints it out, showing the numerical answer to the calculation.

Output

2 * 2 = 4

You can multiply any numbers using the same approach by replacing 2 with any other numbers you want to multiply.

You'll learn more about this as you follow the course, so for now, just click the Next Lesson button and continue your journey.

Hope this helps! Let me know if you have more questions about numbers or anything else you're curious about.

Yes, there’s an important difference between public class and just class in Java. Here’s what you need to know:

1. Accessibility Difference

public class: The class can be accessed from anywhere in your program (even from other packages/folders).

public class Main {  // Can be used everywhere
  public static void main(String[] args) {
    System.out.println("Hello!");
  }
}

class (no modifier): The class is only accessible within its own package/folder.

class Helper {  // Only usable in this package
  void doSomething() { ... }
}

2. File Naming Rule (For public Classes)

If you declare a class as public, the filename must match the class name.

• Name of the file containing public class Main { ... } should be Main.java.

• Name of the file containing public class MyProgram { ... } can't be Main.java.

3. When to Use Which?

• Use public for classes that need to be shared across your project (like Main).

• Use default (class without public) for helper classes that only one package uses.

// File: Main.java (Public, so filename matches)
public class Main {
  public static void main(String[] args) {
    Helper.help();  // Can only call if Helper is public or in same package
  }
}

// File: Helper.java (No 'public' = package-private)
class Helper {
  static void help() {
    System.out.println("Assisting...");
  }
}

Key Takeaway:

• public means anyone can use this class.

• No modifier means only my package/folder can use this class.

That's a good question!

When you look at the output, it can be difficult to notice extra spaces. That's why it's better to check the code carefully.

For example:

print("godfrey sami")

Here, there are no extra spaces before or after the text.

But:

print(" godfrey sami ")

In this case, there are spaces before and after the text — and you can clearly see that by looking at the code.

There are other ways to check for spaces automatically, but for now, we don't want to overwhelm you.

Just click on Next Lesson to keep going!

That's a great question!

Working with SQL is different from entering data into Excel because, with SQL, you don't manually type or organize the data yourself.

Instead, the data is already stored in a database, and you use SQL commands to find, retrieve, organize, and analyze that data automatically.

In Excel, you often work with small amounts of data by hand. In SQL, you can work with huge amounts of data much faster and more efficiently using simple queries.

If you have more questions, I'm here to help!

The reason the numbers 25 and 100 aren’t inside quotes is because they are being treated as numeric values, not text (strings).

In Python, when you put a number inside quotes, it becomes a string—which is a different data type.
If you want to perform calculations like addition, subtraction, or division, you should keep numbers without quotes so Python knows they are numeric values.

In your example:

age = 25
print(age)

age = 100
print(age)

Here, age is initially assigned the numeric value of 25 and later changed to 100. That's why you see them without quotes and why they print as numbers.

Hope this helps! Let me know if you have more questions.

That's a great question!

In Python, int is actually a class, and any number you create (like 1) is an object of that class.

For example, when you write:

number = 1

Here, number is an object of the int class. You can check this using the type() function:

print(type(number))  # Output: 

This shows that int is a class, and every integer you create is an object (or instance) of that class.

Hope this helps!

Fixed values are constants that cannot be changed after they are created, and in the context of strings, they are specific sequences of characters.

For example, when you define a string with either "Python" or 'Python', that exact sequence of characters is what's stored. These strings are fixed values because if you tried to change them—say, by altering the capitalization or adding extra spaces—you would end up with something entirely different.

For instance, "python" (with lowercase 'p') or "Python " (with an extra space after the text and before ") are not the same as "Python".

Hope this helps! If you have any more questions, feel free to ask.

In C, %d is a format specifier used to print integer values. It tells printf(), "Insert an integer here."

For example:

#include 

int main() {

    // Declare and assign an int variable
    int age = 25;

    // Print the value of the variable
    printf("John's age is %d", age);

    return 0;
}

Output

John's age is 25

In printf("John's age is %d", age);, the %d is replaced by the value of age, formatting the output correctly.

You'll come across more format specifiers as you progress in the course.

Let me know if anything is unclear. I'm happy to help.

A string in Python is essentially a sequence of characters. It's used to represent text, and you can think of it as just another way of saying "text" in the programming world.

Whenever you want to work with text data, such as names, messages, or any kind of written content, you would use a string. Strings are enclosed in either single ('...') or double quotes ("..."), and there is no functional difference between using one or the other:

# Examples of strings
name = "Ada"          # Using double quotes
message = 'Hello!'     # Using single quotes

You will learn more about strings in the upcoming chapters. For now, I suggest you continue the course.

Hope this helps!

Great question! In Python, def is a keyword used to define a function.

A function is a block of reusable code that performs a specific task—you define it once and can use it as many times as you like.

Example:

def greet(name):
    print(f"Hello, {name}!")

In the code:

• def tells Python that you're defining a function.

• greet is the name of the function.

• (name) is a parameter the function takes.

• The indented line below it is the function body, which runs when the function is called.

To actually use the function, you'd call it like this:

greet("Alice")  # Output: Hello, Alice!

Why use functions?

• They help you avoid repeating code.

• They make your programs easier to read and maintain.

• You can break a complex task into smaller parts.