# Check if Given Number is power of 2.

**Objective**: Given a number, write a program to find if number is power of two.

**Example**:

N = 5 Output: false. N = 8 Output: true (2^{3}) N = 512 Output: true (2^{9})

**Approach**:

This problem can be solved in multiple ways; we will discuss three solutions here.

- Log
_{2}Method - Check the Remainder
- Convert number to bits

**Log _{2} Method:**

Get the log of the number with base 2 and if outcome is integer then number is power of 2.

**Code**:

**Output**:

Given number 6 is not power of 2 Given number 8 is power of 2 Given number 24 is not power of 2 Given number 512 is power of 2

**Method – Check the Remainder**:

Keep dividing the number by 2 till n =1, and during this iteration if any time number%2 is non zero then number is not power of 2 else the number is power of 2.

**Code**

**Output**:

Given number 6 is not power of 2 Given number 8 is power of 2 Given number 24 is not power of 2 Given number 512 is power of 2

**Method – Bit Manipulation**

- Every number which is a power of 2 has only one bit set (4 = 1 0 0, 8 = 1 0 0 0, 16 = 1 0 0 0 0),
- Convert the given number into binary and count the number of set bits, if count > 1 then number is not power of 2 else the number is power of 2.

**Code**:

**Output**:

Given number 6 is not power of 2 Given number 8 is power of 2 Given number 24 is not power of 2 Given number 512 is power of 2

Reference: Here