力扣算法09——柠檬水找零（贪心算法）

package datasSouce;

public class lemonChange {
    public static void main(String[] args) {
        System.out.println(change(new int[]{5, 5, 10}));
    }
    public static boolean change(int[] nums){
        //20不能找零不用记录
        int five = 0, ten = 0;
        for (int num : nums) {
            if (num == 5){
                five++;
            }else if (num == 10){
                if (five == 0) {
                    return false;
                }else {
                    five--;
                    ten++;
                }
            }else {
                //20
                if (five > 0 && ten > 0) {
                    five--;
                    ten--;
                }else if(five > 3){
                    five -= 3;
                }else {
                    return false;
                }
            }
        }
        return true;
    }
}