4. 51003 - Double Prime

Start: Mar.30.2016 at 03:10:22 PM
Finish: Apr.01.2016 at 05:00:00 AM
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Time limit 2000/4000/4000/4000 ms. Memory limit 65000/65000/65000/65000 Kb.
Question by Ibrahim Mesecan.

Double Prime

A number is prime if it is divisible only by one and itself. A number is Double Prime if the number itself and its digits are prime numbers.

Question: Write a program that counts double prime numbers within the given range.

Input specification
You will be given two numbers: x and y which are between 1 and 40,000,000.

Output specification:
Show the number of double primes within the given range. If there is no double prime number, then show 0 (zero).

Sample Input I
15 30 Sample Output I
1

Explanation: There are four prime numbers between 15 and 30: 17, 19, 23, and 29. But only one of them is double prime: 23.

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