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Online Judge - 10235 - Simply Emirp

來源代碼：UVa
CPE歷屆試題CPE一星
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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!

輸入說明

Input consists of several lines specifying values for N.

輸出說明

資料格式說明

For each N given in the input, output should contain one of the following:

  1. ‘N is not prime.’, if N is not a Prime number.

  2. ‘N is prime.’, if N is Prime and N is not Emirp.

  3. ‘N is emirp.’, if N is Emirp.

輸入輸出範例

範例 1

範例輸入
17
18
19
179
199
範例輸出
17 is emirp.
18 is not prime.
19 is prime.
179 is emirp.
199 is emirp.

範例 2

範例輸入
2
4
11
13
23
範例輸出
2 is prime.
4 is not prime.
11 is prime.
13 is emirp.
23 is prime.

範例 3

範例輸入
101
103
107
121
373
999999
範例輸出
101 is prime.
103 is prime.
107 is emirp.
121 is not prime.
373 is prime.
999999 is not prime.
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