A job, calculating the area of a triangle, the three sides of a side of keyboard input, and determines whether the input with the if statement can form three sides of the triangle.
Ensure the readability of the code, add the code to make a statement out of the area of the triangle only two decimal places. ! [Inserted here described image] ( https://img-blog.csdnimg.cn/20190318224959779.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpc2FtZWFs,size_16,color_FFFFFF,t_70
output: 
Job 2, keyboard input required radius of the circle, and then to calculate the perimeter of the circular area, so that the same statement is added to a print area and perimeter retention triangle two digits, so that play a more simple look at the keyboard input is determined if statement whether conditions constitute circle radius of a circle meet. 
output:
