Degrees of two

It's not a secret that the number 2^n for any nonnegative integer n in binary notation has a very simple form - one in the high bit and then follow n zeros. In the decimal system these numbers are not so unvaried, but even among them there are those that start with one.

Calculate how many such numbers in a given range.

Input

Two integers n[1] and n[2] (0 ≤ n[1] < n[2] ≤ 10^9), separated with a space.

Output

Print, how many numbers are power of two, belong to the range [2^n1; 2^n2] and in decimal notation their first digit is one.

Examples