Problem1230--semi-prime

1230: semi-prime

Time Limit: 1 Sec  Memory Limit: 128 MB
Submit: 53  Solved: 10
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Description

Recently, PIPI is interested in semi-prime numbers. A semi-prime is a number that can be expressed as a product of two prime numbers.For example, 4 and 10 are semi-prime numbers because 4=2×2, 10=2×5. And 8 is not a semi-prime number because 8=2×2×2. He wants to know how many such numbers are in a closed [l,r].
This problem might be hard, can you help PIPI to solve it??

Input

Enter a line containing two numbers l, r(1<=l<=r<=1010, r-l<=105), indicating the closed interval。

Output

The first line is a number n, indicating how many semi-prime numbers there are.
Followed by n lines, each line of three integers pi ai bi, indicating that pi is a semi-prime number, which is the product of two prime numbers ai and bi
The output of the n semi-prime numbers is in increasing order. For each row, ai<=bi。

Sample Input

10 20

Sample Output

3
10 2 5
14 2 7
15 3 5

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