5
24690
1 #include "stdio.h" 2 3 int main(int argc, char const *argv[]) 4 { 5 int n, Sn = 0, num = 2; 6 scanf("%d", &n); 7 8 while(n > 0) 9 { 10 Sn += num; 11 num = num * 10 + 2; 12 n --; 13 } 14 15 printf("%d\n", Sn); 16 return 0; 17 }
原文：http://www.cnblogs.com/hello-lijj/p/7827686.html