题解 | #数列求和#
数列求和
https://www.nowcoder.com/practice/6893484c04c24bfca1f606b1823a468d
public class Main { public static void main(String[] args) { //write your code here........ String num = "9"; long sum=9; for(int i =1;i<10;i++){ num = num+"9"; sum= sum + Long.parseLong(num); } System.out.print(sum); } }