《c++ primer 5th》chapter12-ex12.23_ex12.33

• do while条件语句内要使用的变量必须定义在do while语句外；
• do while条件语句内不能定义任何变量；

Exercise 12.23

Exercise 12.24

Exercise 12.25

Exercise 12.26

Exercise 12.27

Exercise 12.28

Exercise 12.29

Exercise 12.30

Exercise 12.31

Exercise 12.32

Exercise 12.33