1 #include<stdio.h>
 2 void main()
 3 {
 4     int n=0;
 5     double e=1,t=1;//t记录阶乘
 6     char str[65];
 7     printf("n e\n");
 8     printf("- -----------\n");
 9     while(n<=9)
10     {
11         printf("%d ",n);
12         switch(n)
13         {
14         case 0:
15         case 1:
16             printf("%.0lf\n",e);
17             break;
18         case 2:
19             printf("%.1lf\n",e);
20             break;
21         default:
22             printf("%.9lf\n",e);
23             break;
24         }        
25         t*=++n;
26         e += 1.0/t;
27     }
28 }