这道题很简单，主要是弄懂题意和注意输出:
输出的完整结果如下：
n e
- -----------
0 1
1 2
2 2.5
3 2.666666667
4 2.708333333
5 2.716666667
6 2.718055556
7 2.718253968
8 2.718278770
9 2.718281526
java代码如下：
import java.util.*;
import java.io.*; public class Main{ public static void main(String[] arg){
Scanner scan = new Scanner(new BufferedInputStream(System.in));
System.out.println("n e");
System.out.println("- -----------");
for(int i =0 ; i != 10 ; i ++){
if(i<2){
System.out.println(i + " " + (int)getE(i));
}else if(i<3){
System.out.println(i + " " +getE(i));
}else{
System.out.printf("%d %.9f",i,getE(i));
System.out.println();
}
}
scan.close();
} static double getE(int from){
double e = 0;
if(from == 0){
e=1;
}else{
while(from!=0){
e = e + 1.0/getProduct(from);
from--;
}
e +=1;
}
return e;
} static int getProduct(int from){
int p=1;
while(from != 0){
p*=from;
from--;
}
return p;
}
}