In Python programming language, working with long integers or large numbers is a common requirement for various applications. It is important to know how to declare and use long integers efficiently in your code.

In this tutorial, we will walk you through the process of declaring long integers in Python and using them effectively in your programs.

### Step 1: Understanding the Integer Types in Python

In Python 2.x, there were two types of integers – `int`

and `long`

. The `int`

data type was used for numbers that could fit within the range of the machine’s word size, while the `long`

data type was used for larger numbers. However, in Python 3.x, this distinction has been removed, and `int`

can now represent any size of integer. This change makes handling large numbers much easier, as there is no need to worry about the word size when working with integers.

### Step 2: Declaring Long Integer in Python 3

Since Python 3.x now has only one integer type, there is no need to explicitly declare long integers. All integer values, regardless of their size, will automatically be of the `int`

type. Here’s an example:

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large_number = 12345678901234567890 print(type(large_number)) |

The output will be:

class 'int'

As you can see, the `large_number`

variable is of type `int`

, even though it is a large number.

### Step 3: Using Long Integers in Calculations

Now that we know how to declare long integers, we can use them just like any other integer in arithmetic or comparison operations.

For example, let’s perform some calculations with large numbers:

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num1 = 12345678901234567890 num2 = 98765432109876543210 result = num1 + num2 print("Sum:", result) result = num1 * num2 print("Product:", result) result = num1 < num2 print("num1 is smaller than num2:", result) |

The output will be:

Sum: 111111111011111111100 Product: 1219326311126352691126352690 num1 is smaller than num2: True

As you can see, we can perform arithmetic and comparison operations with the long integers just like with any other integers.

## Full Code:

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large_number = 12345678901234567890 print(type(large_number)) num1 = 12345678901234567890 num2 = 98765432109876543210 result = num1 + num2 print("Sum:", result) result = num1 * num2 print("Product:", result) result = num1 < num2 print("num1 is smaller than num2:", result) |

## Conclusion

In conclusion, declaring and using long integers in Python is now simpler, thanks to the unified `int`

data type in Python 3.x.

No special declaration is needed; you can simply assign a large number to a variable and perform calculations just like with any other integer. This feature makes working with large numbers much simpler and more efficient in your Python applications.