Pairwise AND

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Given a number $N$, consider all whole numbers $\leq N$, ie, $(0, 1, …, N)$. Find the sum of the bitwise AND of all consecutive numbers. For example, the bitwise AND of $5 = 101_2$ and $7 = 111_2$. $(5 \& 7) = (101_2 \& 111_2) = 101_2 = 5$. Since this sum can very large, print the final answer modulo $10^9 + 7$. (Note: Be careful of overflows while dealing with large numbers.) ##

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solution.cppC++17

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