import java.util.*;

public class Solution {

    public int solution(int[] A, int[] B){
        Map<Integer, Integer> mappedIntervals = prepareMap(A, B);
        Integer[] keyArray = mappedIntervals.keySet().toArray(new Integer[mappedIntervals.size()]);
        ArrayList<Integer> keyArrayList = new ArrayList<>(Arrays.asList(keyArray));
        int begginingFirst, endingFirst, begginingSecond, endingSecond;
        int iterator = 0;
        while(iterator < keyArrayList.size()-1){
            begginingFirst = keyArrayList.get(iterator);
            endingFirst = mappedIntervals.get(begginingFirst);
            begginingSecond = keyArrayList.get(iterator+1);
            endingSecond = mappedIntervals.get(begginingSecond);
            if((begginingSecond <= endingFirst) && (endingSecond >= endingFirst)){
                mappedIntervals.put(begginingFirst, endingSecond);
                mappedIntervals.remove(begginingSecond);
                keyArrayList.remove(iterator+1);
            }
            else{
                iterator++;
            }
        }
        return mappedIntervals.size();
    }

    private Map<Integer, Integer> prepareMap(int[] A, int[] B){
        Map<Integer, Integer> mappedIntervals = new TreeMap<>();
        for(int i = 0; i<A.length; i++){
            mappedIntervals.put(A[i], B[i]);
        }
        return mappedIntervals;
    }

    public static void main(String[] args){
        Solution solution = new Solution();
        int result =  solution.solution(new int[]{1, 12, 42, 70, 36, -4, 43, 15}, new int[]{5, 15, 44, 72, 36, 2, 69, 24});
        System.out.println(result);
    }
}