Solution of 10242 - Fourth Point !!

Problem Description
source:https://uva.onlinejudge.org/external/102/10242.html

Given are the (x, y) coordinates of the endpoints of two adjacent sides of a parallelogram. Find the (x, y) coordinates of the fourth point. 

Input 

Each line of input contains eight floating point numbers: the (x, y) coordinates of one of the endpoints of the first side followed by the (x, y) coordinates of the other endpoint of the first side, followed by the (x, y) coordinates of one of the endpoints of the second side followed by the (x, y) coordinates of the other endpoint of the second side. All coordinates are in meters, to the nearest mm. All coordinates are between −10000 and +10000. Input is terminated by end of file. 

Solution of 10235 - Simply Emirp

Problem Description
source:https://uva.onlinejudge.org/external/102/10235.html

An integer greater than 1 is called a prime number if its only positive divisors (factors) are 1 and itself. Prime numbers have been studied over the years by a lot of mathematicians. Applications of prime numbers arise in Cryptography and Coding Theory among others. 
      Have you tried reversing a prime? For most primes, you get a composite (43 becomes 34). An Emirp (Prime spelt backwards) is a Prime that gives you a different Prime when its digits are reversed. For example, 17 is Emirp because 17 as well as 71 are Prime. 
     In this problem, you have to decide whether a number N is Non-prime or Prime or Emirp. Assume that 1 < N < 1000000. 
     Interestingly, Emirps are not new to NTU students. We have been boarding 199 and 179 buses for quite a long time!