# bin() in Python

Converting an decimal to binary is always an important utility that is required in python dev projects and competitive programming as well. Having a shorthand function to achieve this can always be handy in the situations which require the swift conversion of it without writing a long code for same, this is provided by “bin()“. This has been discussed in this article.

Naive Methods to convert decimal to binary

1. Using recursion

 `# Function to print binary number for the  ` `# input decimal using recursion ` `def` `decimalToBinary(n): ` ` `  `    ``if` `n > ``1``: ` `        ``# divide with integral result  ` `        ``# (discard remainder)  ` `        ``decimalToBinary(n``/``/``2``)  ` ` `  ` `  `    ``print` `(n``%``2``,end``=``"")          ` ` `  `# Driver code ` `if` `__name__ ``=``=` `'__main__'``: ` `    ``decimalToBinary(``8``) ` `    ``print``(``"\r"``) ` `    ``decimalToBinary(``18``) ` `    ``print``(``"\r"``) ` `    ``decimalToBinary(``7``) ` `    ``print`

Output :

```1000
10010
111
```

2. Using loop

 `# Python code to demonstrate naive method ` `# using loop  ` ` `  `# function returning binary string ` `def` `Binary(n): ` `    ``binary ``=` `"" ` `    ``i ``=` `0` `    ``while` `n > ``0` `and` `i<``=``8``: ` `        ``s1 ``=` `str``(``int``(n``%``2``)) ` `        ``binary ``=` `binary ``+` `s1 ` `        ``n ``/``=` `2` `        ``i ``=` `i``+``1` `        ``d ``=` `binary[::``-``1``] ` `    ``return` `d ` ` `  `print``(``"The binary representation of 100 (using loops) is : "``,end``=``"") ` `print``(Binary(``100``)) `

Output:

```The binary representation of 100 (using loops) is : 001100100
```

Using bin()

Using bin() reduces the time required to code and also removes the hassle that you may see in the above two mentioned methods.

```Syntax :
bin(a)
Parameters :
a : an integer to convert
Return Value :
A binary string of an integer or int object.
Exceptions :
Raises TypeError when a float value is sent in arguments.
```

 `# Python code to demonstrate working of ` `# bin() ` ` `  `# function returning binary string ` `def` `Binary(n): ` `    ``s ``=` `bin``(n) ` `     `  `    ``# removing "0b" prefix ` `    ``s1 ``=` `s[``2``:] ` `    ``return` `s1 ` ` `  `print``(``"The binary representation of 100 (using bin()) is : "``,end``=``"") ` `print``(Binary(``100``)) `

Output :

```The binary representation of 100 (using bin()) is : 1100100
```

This article is contributed by Manjeet Singh. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.