练习（Assignment）

1.(Level 1)Using condition flow control, write a program called IfTest to test whether a number is positive, negative or 0.

（级别1）使用条件流程控制语句，写一个IfTest.java程序来判断一个数字是正数、负数还是零。

2.(Level 2)Using while/do-while/for loop flow control respectively, write a program called LoopTest to multiply 1 to 10 and print out the result.

（级别2）分别使用while/do-while/for循环流程控制语句，写一个LoopTest.java程序来计算10的阶乘（从1乘到10）并打印结果。