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How to convert a decimal number to binary in Python

How to convert a decimal number to binary in Python.

Here's a detailed step-by-step tutorial on how to convert a decimal number to binary in Python:

Step 1: Understand the Decimal and Binary Number Systems​

Before we dive into the code, it's important to understand the decimal and binary number systems. The decimal system is a base-10 system, meaning it uses 10 digits (0-9) to represent numbers. On the other hand, the binary system is a base-2 system, using only two digits (0 and 1) to represent numbers.

Step 2: Plan the Conversion Process​

To convert a decimal number to binary, we need to repeatedly divide the decimal number by 2 and keep track of the remainders. The binary representation of the decimal number is formed by arranging the remainders in reverse order.

Step 3: Initialize Variables​

We'll start by initializing two variables: decimal to store the decimal number we want to convert, and binary to store the binary representation.

decimal = 42  # Example decimal number
binary = ""

Step 4: Perform the Conversion​

Now, let's write a loop to perform the conversion. Inside the loop, we'll divide the decimal number by 2 using integer division (//) and keep track of the remainder using the modulo operator (%). We'll then add the remainder to the binary string.

while decimal > 0:
    remainder = decimal % 2
    binary = str(remainder) + binary
    decimal = decimal // 2

Step 5: Display the Result​

Finally, we'll display the binary representation of the decimal number:

print("Binary: " + binary)

Step 6: Test the Code​

Let's put everything together and test the code with an example decimal number, such as 42. Here's the complete code:

decimal = 42
binary = ""

while decimal > 0:
    remainder = decimal % 2
    binary = str(remainder) + binary
    decimal = decimal // 2

print("Binary: " + binary)

When you run the code, it should output:

Binary: 101010

Congratulations! You have successfully converted a decimal number to binary in Python.

Additional Example:​

Let's convert another decimal number, such as 123, to binary. Here's the updated code:

decimal = 123
binary = ""

while decimal > 0:
    remainder = decimal % 2
    binary = str(remainder) + binary
    decimal = decimal // 2

print("Binary: " + binary)

When you run the updated code, it should output:

Binary: 1111011

That's it! You can now convert decimal numbers to binary using Python.