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Problem B
EvenOdd

Consider the following function f(X), which takes a single positive integer as argument, and returns an integer.

function f(X):
    iterations := 0
    while X is not 1:
        if X is even:
            divide X by 2
        else:
            add 1 to X
        add 1 to iterations
    return iterations

It can be shown that for any positive integer X, this function terminates. Given an interval [L,R], compute the sum

S=f(L)+f(L+1)++f(R1)+f(R).

Input

The first and only line of input contains two integers L and R (1LR1018).

Output

Output the result S modulo the prime 109+7.

Sample Input 1 Sample Output 1
1 127
1083
Sample Input 2 Sample Output 2
74 74
11
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