题解 | 数列求和
public class Main {
public static void main(String[] args) {
//write your code here........
long n = 9;
long sum = 9;
long m;
for (int i = 1; i <10; i++) {
m = (long)Math.pow(10, i);
n = n + m*9;
sum += n;
}
System.out.println(sum);
}
}
循环九次
