Granny's Puzzle II

Time Limit: 1 sec

**The Problem**

**Anna **is enjoying her time in her grandma’s house. Today **granny **is making **Anna’s** favourite apple pie and **Anna **is helping her. Just to enjoy the time **grandma **asked **Anna **can you solve a simple puzzle of mine? **Anna **agreed joyfully.

**Grandma **said well **Anna **suppose there are 5 apples in different weights. You have to sort them according their weights then have to pick the middle one which I goanna use in your apple pie.

**The Input**

**The Input file contains several test cases. Each case contains 5 floating numbers, weight of 5 apples. The range is in between -100 to 100. The input file is terminated by EOF.**

**The Output**

**For each line of input you have to print the middle one’s weight rounded to 2 decimal points. As you know 0 and (-) minus value can’t be the weight. For this kind of input print “Invalid” in a separate line. **

**Sample Input**

1.12 2.56 3.25 2.56 0.34

-1.20 -2.56 6.34 0.00 1.56

**0.00 1.00 2.00 3.00 4.00**

**Sample Output**

Case 1: 2.56

Case 2: Invalid

**Case 3: Invalid**

Problem Setter: Samia Safa Ahmed