class Solution {
    public boolean lemonadeChange(int[] bills) {
        int five = 0;
        int ten = 0;
        for (int i = 0; i < bills.length ; i++) {
            if (bills[i] == 5) {
                five++;
            } else if (bills[i] == 10) {
                five--;
                ten++;
            } else if (bills[i] == 20) {
                if (ten>0) {
                    ten--;
                    five--;
                } else{
                    five -=3;
                }
            }
            if (five < 0 || ten < 0) {
                return false;
            }
        }
        return true;
    }
}

public int[][] reconstructQueue(int[][] people) {
	Arrays.sort(people, (a,b) -> a[0] == b[0] ? a[1] - b[1] : b[0] - a[0]);

	List<int[]> ordered = new LinkedList<>();
	for (int[] p: people) ordered.add(p[1], p);

	return ordered.toArray(new int[people.length][2]);
}

class Solution {
    public int findMinArrowShots(int[][] points) {
        Arrays.sort(points, (a, b) -> Integer.compare(a[0], b[0]));

        int count = 1;  
        for (int i = 1; i < points.length; i++) {
            if (points[i][0] > points[i - 1][1]) {  
                count++; 
            } else {  
                points[i][1] = Math.min(points[i][1], points[i - 1][1]); 
            }
        }
        return count;
    }
}