find max key value in map in kotlin

1public class NewClass4 {
2    public static void main(String[] args)
3    {
4        HashMap<Integer,Integer>map=new HashMap<Integer, Integer>();
5        map.put(1, 50);
6        map.put(2, 60);
7        map.put(3, 30);
8        map.put(4, 60);
9        map.put(5, 60);
10        int maxValueInMap=(Collections.max(map.values()));  // This will return max value in the Hashmap
11        for (Entry<Integer, Integer> entry : map.entrySet()) {  // Itrate through hashmap
12            if (entry.getValue()==maxValueInMap) {
13                System.out.println(entry.getKey());     // Print the key with max value
14            }
15        }
16
17    }
18}

1fun max(map:Map<Int,String>) =  map.maxByOrNull { it.key }?.key ?:-1//returns negative one if the max is null
2fun main(){
3var map = mapOf(1 to "hello",2 to "peace", 3 to "ochuko")
4    println(map.maxByOrNull { it.key }?.key ?:-1)
5}

1//For kotlin
2fun max(map:Map<Int,String>) =  map.maxByOrNull { it.key }?.key ?:-1//returns negative one if the max is null
3fun main(){
4var map = mapOf(1 to "hello",2 to "peace", 3 to "ochuko")
5    println(map.maxByOrNull { it.key }?.key ?:-1)
6}