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blog_posts/python-swap-variables.md

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+---
+title: 3 ways to swap two variables in Python
+type: story
+tags: python,variables
+authors: maciv
+cover: blog_images/leaves-read.jpg
+excerpt: Learn 3 easy ways to swap the values of two variables in Python.
+---
+
+### Using a temporary variable
+
+The simplest way to swap the values of two variables is using a `temp` variable. The `temp` variables is used to store the value of the fist variable (`temp = a`), allowing you to swap the value of the two variables (`a = b`) and then assign the value of `temp` to the second variable.
+
+```python
+a = 11
+b = 7
+
+temp = a
+a = b
+b = temp
+
+print(a) # 7
+print(b) # 11
+```
+
+### Without a temporary variable (Tuple swap)
+
+Another way to swap the values of two variables, without using a temporary variable, is to use tuple packing and sequence unpacking. Tuples can be constructed in a number of ways, one of which is by separating tuple items using commas. Moreover, Python evaluates the right-hand side of an assignment before its left-hand side. So, by separating the variables with commas on the right side of the statement the variables are packed into a tuple and unpacked by placing the same number of comma-separated target variables on the left side.
+
+This method of variable swapping and permutation can be used for more than two variables as long as the same number of variables are on both sides of the statement.
+
+```python
+a = 11
+b = 7
+
+a, b = b, a
+
+print(a) # 7
+print(b) # 11
+```
+
+### Using arithmetic operators (for numbers only)
+
+If the two variables are numbers, their values can be swapped using arithmetic operators such as addition and subtraction (`+`, `-`) or multiplication and division (`*`, `/`). This swapping method is based on calculating the sum of the two numbers and then swapping them using the sum and the difference from the sum.
+
+```python
+a = 11
+b = 7
+
+a = a + b # a = 18, b = 7
+b = a - b # a = 18, b = 11
+a = a - b # a = 7,  b = 11
+
+print(a) # 7
+print(b) # 11
+```
+
+**Image credit:** [Thought Catalog](https://unsplash.com/@thoughtcatalog?utm_source=unsplash&utm_medium=referral&utm_content=creditCopyText) on [Unsplash](https://unsplash.com?utm_source=unsplash&utm_medium=referral&utm_content=creditCopyText)