java for，while,do while循环三种概念

 while循环

public class SettleAccountUsingWhile {
    public static void main(String[] args) {
        int times = 5;
        while (times > 0) {
            int price = 5;
            int amount = 10;
            if (price > 0 && amount > 0) {
                int totalCost = price * amount;
                System.out.println(totalCost);
            } else {
                System.out.println("price和amount的值必须都大于0，否则无法计算");
            }
            times = times - 1;
        }
        System.out.println("while循环语句执行结束，结账员可以休息一下了。");
    }
}

for循环

public class SettleAccountUsingfor {
    public static void main(String[] args) {
        for (int times = 0; times <= 5; times++) {
            int price = 5;
            int count = 10;
            if (price > 0 && count > 0) {
                int totalCost = price * count;
                System.out.println(totalCost);
            } else {
                System.out.println("当price和count同时大于0时，才可以执行for循环");
            }
        }
        System.out.println("for循环执行结束，工作人员可以休息了");
    }
}

do while循环

public class SettleAccountUsingdowhile {
    public static void main(String[] args) {
        int times = 5;
        do {
            int price = 5;
            int count = 10;
            if (price > 0 && count > 0) {
                int totalprice = price * count;
                System.out.println(totalprice);
            } else {
                System.out.println("price和count的值必须都大于0，否则执行不了do while 循环");
            }
            times = times - 1;
        } while (times > 0);
        System.out.println("do while 循环执行结束，可以休息一下了");
    }
}