What are the rules for declaring Swift variables?

In Swift, the rules for declaring variables are as follows:

1. variable
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4. The type of a variable can be explicitly declared or inferred from the initial value.

For example, the code for declaring an integer variable and assigning it an initial value is as follows:

var age: Int = 25

You can also omit the declaration of variable type and let the compiler infer the type based on the initial value, for example:

var age = 25

In this scenario, the compiler will automatically infer age as an integer variable.