# 
## Problem Statement

Given a number `n`, find the highest power of 2 that is smaller than or equal to `n`.

**Example 1:**
- Input: n=5
- Output: 4

**Example 2:**
- Input: n=25
- Output: 16

**Example 3:**
- Input: n=32
- Output: 32

# 
## Solution 

The simplest solution is to start with powers of `2` from 1, such as 2<sup>1</sup>. For every power of two, check if it's greater than the given number. If it's greater than the given number, then return the previous/last power of two.



## Example

class Main{

    static int highestPowerofTwoLessThanN(int n) {
        if (n < 1) return 0;

        int pow = 1;

        while((1 << pow) <= n) pow++;

        return (1 << (pow - 1));
    }

    public static void main (String[] args) {
        int n = 10;
        System.out.println("The highest power of 2 less than " + n + " is " + highestPowerofTwoLessThanN(n));
    }
}

# 
## Code explanation

- **Line 4**: If `n` is less than `1`, then return zero.
- **Line 6**: Initialize the `power` variable to `1`.
- **Line 8**: While 2<sup>power</sup> is less than or equal to `n`, increment the power value by `1`.
- **Line 10**: Once the control is out of the `while` loop, it means that we have a power of two that is greater than `n`. Hence, we return the power of two for the last/previous power value.
- **Line 14**: The `n` number is defined.

Highest power of 2 less than or equal to given number

For a given n, find the highest power of 2 ≤ n by iterating powers of 2 until surpassing n.

Highest power of 2 less than or equal to given number

Problem Statement

Solution

Example

Code explanation

Complexity analysis