Count Total Set Bits - InterviewBit Solution

Problem Description:

Given a positive integer A, the task is to count the total number of set bits in the binary representation of all the numbers from 1 to A
Return the count modulo 109 + 7.

Problem Constraints

1 <= A <= 109

Input Format

The first and only argument is an integer A.

Output Format

Return an integer denoting the ( Total number of set bits in the binary representation of all the numbers from 1 to A )modulo 109 + 7.

Example Input

Input 1:
A = 3
Input 2:
A = 1

Example Output

Output 1:
4
Output 2:
1

Example Explanation

Explanation 1:

DECIMAL BINARY SET BIT COUNT
1 01 1
2 10 1
3 11 2
1 + 1 + 2 = 4
Answer = 4 % 1000000007 = 4

Explanation 2:

A = 1
DECIMAL BINARY SET BIT COUNT
1 01 1
Answer = 1 % 1000000007 = 1

Solution Approach:

Solution in C++:

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