Problem 2L. List of Primes

Author:NEERC 2016   Time limit:2 sec
Input file:input.txt   Memory limit:512 Mb
Output file:output.txt  

Statement

Lidia likes sets of prime numbers. When she is bored, she starts writing them down into the Extremely Long Notebook for Prime Sets.

Elements of each set are written down in ascending order. Each set of prime numbers appears in her notebook eventually. A set with a smaller sum always appears before a set with a larger sum. Sets with the same sum are sorted in ascending lexicographical order: they are compared by the first element, if the first elements are equal, then by second element, and so on.

Just in case someone decides to parse her notebook, she writes down her sets in a machine-readable JSON format. Of course, she puts a space after each comma. Here's the beginning of her notebook:

[2], [3], [2, 3], [5], [2, 5], [7], [3, 5], [2, 7], [2, 3, 5], [3, 7], [11], [2, 3, 7], [5, 7], [2, 11], [13], [2, 5, 7],

Lidia wants to double-check her work, so here is her request for you: given two integers, a and b, output a substring of her notebook from the position a to the position b (inclusive, counting from 1).

Input file format

The first line contains two integers, a and b (1 ≤ a ≤ b ≤ 1018; b − a ≤ 105).

Output file format

Output the substring of the notebook described in the problem statement from the position a to the position b. You must write a line with exactly b − a + 1 characters, including any leading and/or trailing spaces.

Constraints

Sample tests

No. Input file (input.txt) Output file (output.txt)
1
1 35
[2], [3], [2, 3], [5], [2, 5], [7],
2
36 41
 [3, 5

0.085s 0.009s 13