package com.study.demo; public class test3_1_99 { public static void main(String[] args) { int[] numbers = new int[99]; for (int i = 0; i < numbers.length; i++) { numbers[i] = i + 1; } int sum = 0; for (int i = 0; i < numbers.length; i++) { sum += numbers[i]; } System.out.println("1+2+...+99 的和 = " + sum); } }