In this program, you'll learn to find the largest among three numbers using if else and when statement in Kotlin.

```
fun main(args: Array<String>) {
val n1 = -4.5
val n2 = 3.9
val n3 = 2.5
if (n1 >= n2 && n1 >= n3)
println("$n1 is the largest number.")
else if (n2 >= n1 && n2 >= n3)
println("$n2 is the largest number.")
else
println("$n3 is the largest number.")
}
```

When you run the program, the output will be:

3.9 is the largest number.

In the above program, three numbers `-4.5`

, `3.9`

and `2.5`

are stored in variables `n1`, `n2` and `n3` respectively.

Then, to find the largest, the following conditions are checked using if else statements

- If
`n1`is greater or equals to both`n2`and`n3`,`n1`is the greatest. - If
`n2`is greater or equals to both`n1`and`n3`,`n2`is the greatest. - Else,
`n3`is the greatest.

The greatest number can also be found using a `when`

statement.

Here's the equivalent Java code: Java Program to Find the Largest Among Three Numbers

```
fun main(args: Array<String>) {
val n1 = -4.5
val n2 = 3.9
val n3 = 5.5
when {
n1 >= n2 && n1 >= n3 -> println("$n1 is the largest number.")
n2 >= n1 && n2 >= n3 -> println("$n2 is the largest number.")
else -> println("$n3 is the largest number.")
}
}
```

When you run the program, the output will be:

5.5 is the largest number.

In the above program, instead of using `an if..else if..else`

block, we use `when`

statement.

So, the above conditions in both the programs are the same.