Concatenation of Consecutive Binary Numbers
Medium
Provided an integer n , produce the decimal value of the binary string formed by concatenating the binary representations of 1 to n in order, modulo 10^9 + 7 .
Example 1
Input: n = 1
Output: 1
Explanation: In this case, "1" in binary corresponds to the decimal value 1.
Example 2
Input: n = 3
Output: 27
Explanation: In this case, in binary, 1, 2, and 3 corresponds to "1", "10", and "11".
After concatenating them, we have "11011", which corresponds to the decimal value 27.
Example 3
Input: n = 12
Output: 505379714
Explanation: The concatenation results in "1101110010111011110001001101010111100".
The decimal value of that is 118505380540.
After modulo 10^9 + 7, the result is 505379714.
Constraints
1 <= n <= 10^5
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