Your new Math teacher Mr. Primeman has intersting problem for you . He gave you two sets S1 and S2 such that each consists of
squares of positive integers . Now Mr. Primeman asks you to find prime numbers which can be written as sum of two numbers x and y where
x belongs to S1 and y belongs to S2. Now given a range [a,b] , find count of such numbers .

Input
One line containing two numbers a and b respectively.

Output
For range ,output the required answer with newline.

Constraints
0 ≤ a ≤ b ≤ 2*(10^8)
Example

SAMPLE INPUT
10 15

SAMPLE OUTPUT
1

Explanation

There are only two prime numbers 11 and 13 between [10,15] while only 13 satisfies the condition 13=2^2+3^2=4+9.

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