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kotlinlang

My Code
```fun changeIntToDouble(number: Int) {
    return number.toDouble()
}```
but my ide said Type mismatch: inferred type is Int but Unit was expected
How can I fix it?

If you don't explicitly specify a return type it defaults to `Unit`, i.e. "nothing".

You need to explicitly define it as:
```fun changeIntToDouble(number: Int): Double {```

Or write it as expresssion body like
```fun changeIntToDouble(number: Int) = number.toDouble()```

^ That works too, although my understanding is that too many inferred return types can make IntelliJ slow.