16. **Poisonous Plants

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayDeque;
import java.util.Arrays;

public class Main {

    public static void main(String[] args) throws IOException {

        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        int initialPlantsCount = Integer.parseInt(reader.readLine());

        int[] plants = Arrays.stream(reader.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();

        short[] days = new short[initialPlantsCount];

        ArrayDeque<Integer> temp = new ArrayDeque<>();
        temp.push(0);
        short maxDay=0;

        for (int i = 1; i < initialPlantsCount; i++) {

            short maxDays = 0;
            while (temp.size() > 0 && plants[temp.peek()] >= plants[i]) {
                maxDays = (short) Math.max(maxDays, days[temp.pop()]);
            }
            if (temp.size() > 0) {

                days[i] = ++maxDays;
                if(days[i]>maxDay){
                    maxDay=days[i];
                }
            }
            temp.push(i);
        }
        System.out.println(maxDay);
    }
}