A - Circular
Problem
A circular prime is a prime number that remains prime as each leftmost digit (most significant digit), in turn, is moved to the right hand side. For instance, the number 19937 is a circular prime, since all numbers in the sequence 19937, 99371, 93719, 37199 and 71993 are prime numbers. Your objective is to write a program that, given a range, computes the number of circular primes in that range.
Input
The input consists of a sequence
of pairs of integers i and j, with one pair of
integers per input line. All integers will be less than 1,000,000 and greater
or equal to 100. You can assume that in any pair i is lesser or equal than j. You should process all pairs of
integers, and for each such pair, count the number of circular primes between i and j, including i and j. Input
is terminated by a line just with the number -1.
Output
For each pair of input integers, defining a range, the output should be: “No Circular Primes.” (if there are no circular primes in the range), “1 Circular Prime.” (if only one circular prime exists in the range), or “n Circular Primes.” (if there are n circular primes in the range, and n is greater than one).
Sample Input
1000
1100
100
120
100
1000
-1
Sample Output
No
Circular Primes.
1 Circular Prime.
12 Circular Primes.