Decrement by One

Decrement by One

To decrement the value of a variable by one in Python, we can use Subtraction Assignment operator, and pass the variable and value 1 as operands to it.

Syntax

The syntax to decrement the value of x by one is

x -= 1

This is just a short hand for the following assignment statement.

x = x - 1

We can use the above syntax as well to decrement the value of a variable by one.

Example

In this example, we will read a number into x from user, and decrement the value in x by one using Subtraction Assignment operator.

Python Program

x = int(input('enter a number : '))
x -= 1
print('after decrement :', x)

Output

enter a number : 4
after decrement : 3

Summary

In this tutorial of Python Examples, we learned how to decrement the value of a variable by one.