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You are given two numbers **A** and **B**. The task is to **count the number of bits needed to be flipped **to **convert **A to B.

**Example 1****:**

**Input: **A = 10, B = 20
**Output**: 4
**Explanation**:
A = 01010
B = 10100
As we can see, the bits of A that need
to be flipped are **0101**0. If we flip
these bits, we get 10100, which is B.

**Example 2:**

**Input**: A = 20, B = 25
**Output**: 3
**Explanation**:
A = 10100
B = 11001
As we can see, the bits of A that need
to be flipped are 1**01**0**0**. If we flip
these bits, we get 11001, which is B.

**Your Task: **The task is to complete the function **countBitsFlip**() that **takes A and B** as parameters and **returns **the **count **of the **number of bits to be flipped** to convert** A to B**.

**Expected Time Complexity:** O(log N).

**Expected Auxiliary Space:** O(1).

**Constraints:**

1 ≤ A, B ≤ 10^{6}

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