# 18 bit signed binary number to decimal in python

Converting a signed binary number to decimal in Python can be achieved in several ways. In this article, we will explore three different approaches to solve this problem.

## Approach 1: Using built-in functions

``````
def binary_to_decimal(binary):
decimal = int(binary, 2)
return decimal

binary_number = "10010"
decimal_number = binary_to_decimal(binary_number)
print(decimal_number)
``````

In this approach, we utilize the built-in function `int()` with base 2 to convert the binary number to decimal. The function takes two arguments – the binary number and the base. The resulting decimal number is then returned.

## Approach 2: Manual conversion

``````
def binary_to_decimal(binary):
decimal = 0
power = len(binary) - 1
for digit in binary:
decimal += int(digit) * (2 ** power)
power -= 1
return decimal

binary_number = "10010"
decimal_number = binary_to_decimal(binary_number)
print(decimal_number)
``````

In this approach, we manually convert the binary number to decimal by iterating over each digit of the binary number. We calculate the decimal value by multiplying each digit with the corresponding power of 2 and summing them up.

## Approach 3: Using bitwise operations

``````
def binary_to_decimal(binary):
decimal = 0
for digit in binary:
decimal = (decimal << 1) | int(digit)
return decimal

binary_number = "10010"
decimal_number = binary_to_decimal(binary_number)
print(decimal_number)
``````

In this approach, we utilize bitwise operations to convert the binary number to decimal. We shift the decimal number to the left by 1 bit and then perform a bitwise OR operation with the current digit of the binary number. This process is repeated for each digit, resulting in the decimal representation.

After evaluating all three approaches, it can be concluded that Approach 1, which utilizes the built-in function `int()`, is the most efficient and concise solution. It leverages the power of Python's built-in functions, resulting in a simpler and more readable code.

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### 12 Responses

1. Amiri Cooper says:

Approach 1 seems straightforward, but I wonder if Approach 3 can be more efficient. Thoughts?

1. Clayton says:

Ive tried both approaches extensively and Approach 1 always delivers better results. Approach 3 might sound appealing, but in reality, its just an unnecessary complication. Stick with what works, my friend.

2. Kylan says:

Approach 2 sounds cool, but Approach 3 with bitwise operations seems like a secret code-breaking party! 🧐🔢

3. Cleo says:

Approach 2 seems fun, but Approach 3 with bitwise operations is like a secret code!

Approach 2 may be fun, but Approach 3 with bitwise operations is on a whole different level. Its like speaking a secret code that only the elite few can understand. Unlocking the mysteries of bitwise operations adds an extra layer of intrigue to programming.

4. Emilia says:

Approach 2 seems more tedious, but maybe its worth it for the learning experience? 🤔

5. Bria Spears says:

Approach 2 seems like a brain exercise, but Approach 1 is time-saving. What do you guys think?

6. Zora Salazar says:

Approach 2 seems more challenging but rewarding, like solving a puzzle! Whos up for it? 🧩

7. Arabella Peralta says:

Approach 3 seems like a confusing maze of bitwise operations! Who needs that complexity?

8. Diana says:

Approach 2 seems like a brain teaser! Who knew manual conversion could be so fun!

9. Jada Montoya says:

Approach 2 seems old school, but sometimes going manual can be oddly satisfying! 🤓

10. Laila says:

Approach 2 seems more fun, like a puzzle to solve! Whos with me? 🧩😄