java - 不打印循环中的某个元素

Question

所以我有以下代码:

public class MyClass {
    public static void main(String args[]) {
        Scanner reader = new Scanner(System.in);

        System.out.println("Enter the upper limit: ");
        int input = reader.nextInt();

        int i = 0;
        int power = 1;
        long sum;

        while (i <= input) {
            System.out.print(power + " + ");
            sum = power + power;
            power = power * 2;
            i++;

            if (power > input) {
                System.out.print(" = " + sum);
                System.exit(0);
            }
        }
    }
}

假设用户输入 500。

输出将是:

1 + 2 + 4 + 8 + 16 + 64 + 128 + 256 + = 512

我想去掉最后一个“+”，这样它看起来就像一个实际的方程。

Answer 1

只需在else语句中添加打印+

 Scanner reader = new Scanner(System.in);

    System.out.println("Enter the upper limit: ");
    int input = reader.nextInt();

    int i = 0;
    int power = 1;
    long sum;

    while (i <= input) {
        System.out.print(power);
        sum = power + power;
        power = power * 2;
        i++;

        if (power > input) {
            System.out.print(" = " + sum);
            System.exit(0);
        }else {
            System.out.print(" + ");
        }
    }

输出

1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 = 512