# Different ways to Invert the Binary bits in Python

• Difficulty Level : Easy
• Last Updated : 20 Aug, 2020

We know how binary value for numbers look like. For example, the binary value for 10 (Number Ten) is 1010 (binary value).

Sometimes it is required to inverse the bits i.e., 0’s to 1’s ( zeros to ones) and 1’s to 0’s (ones to zeros). Here are there few ways by which we can inverse the bits in Python.

1) Using Loops: By iterating each and every bit we can change the bit 1 to bit 0 and vice-versa.

## Python3

 `bit_s ``=` `'1010'``inverse_s ``=` `''`` ` `for` `i ``in` `bit_s:``   ` `    ``if` `i ``=``=` `'0'``:``        ``inverse_s ``+``=` `'1'``         ` `    ``else``:``        ``inverse_s ``+``=` `'0'``         ` `print``(``"Inversed string is "``,``      ``inverse_s)`

Output:

```Inversed string is 0101
```

2) Using Dictionary: Dictionaries are very fast in accessing an element, which it takes O(1) time complexity.

## Python3

 `# create a dictionary``b_dict ``=` `{``'0'``: ``'1'``, ``'1'``: ``'0'``}`` ` `bit_s ``=` `'1010'`` ` `inverse_s ``=` `''`` ` `for` `i ``in` `bit_s:``   ` `    ``inverse_s ``+``=` `b_dict[i]``     ` `print``(``"Inversed string is"``,``      ``inverse_s)`

Output:

```Inversed string is 0101
```

3) Using List comprehension: List comprehensions are the short hand notations of accessing, adding, manipulating a list.

## Python3

 `bit_s ``=` `'1010'`` ` `# using ternary operator with ``# list comprehension``inverse_s ``=` `'``'.join(['``1``' if i == '``0``' else '``0``'``                     ``for` `i ``in` `bit_s])`` ` `print``(``"Inversed string is"``, ``      ``inverse_s)`

Output:

```Inversed string is 0101
```

4) Using replace() method of strings: In python, strings has a built-in method i.e., string.replace(existing_characters, new_characters), which replaces all the existing_characters with new_characters.

## Python3

 `bit_s ``=` `'1010'`` ` `# replace "1" with "2" ``# output : "2020"``inverse_s ``=` `bit_s.replace(``'1'``, ``'2'``)`` ` `# replace "0" with "1" ``# output : "2121"``inverse_s ``=` `inverse_s.replace(``'0'``, ``'1'``)`` ` `# replace "0" with "1" ``# output : "0101"``inverse_s ``=` `inverse_s.replace(``'2'``, ``'0'``)`` ` `print``(``"Inversed string is"``, ``      ``inverse_s)`

Output:

```Inversed string is 0101
```

5) Using bit-wise XOR operator: XOR operator Returns 1 if one of the bit is 1 and other is 0 else returns false.

## Python3

 `bit_s ``=` `'1010'`` ` `# convert binary string ``# into integer``temp ``=` `int``(bit_s, ``2``)`` ` `# applying Ex-or operator``# b/w 10 and 31``inverse_s ``=` `temp ^ (``2` `*``*` `(``len``(bit_s) ``+` `1``) ``-` `1``)`` ` `# convert the integer result ``# into binary result and then ``# slicing of the '0b1' ``# binary indicator``rslt ``=` `bin``(inverse_s)[``3` `: ]`` ` `# print the result``print``(``"Inversed string is"``, ``      ``rslt )`

Output:

```Inversed string is  0101
```

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