Java 程序求和：1+(1+2)+(1+2+3)+...+(1+2+3+...+n) - 使用 While 循环

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int sum = 0;
        int i = 1, j = 1;
        while (i <= n) {
            while (j <= i) {
                sum += j;
                j++;
            }
            i++;
            j = 1;
        }
        System.out.println(sum);
    }
}