# 1342-number-of-steps-to-reduce-a-number-to-zero


Try it on <a href='https://leetcode.com/problems/1342-number-of-steps-to-reduce-a-number-to-zero'>leetcode</a>

## Description
<div class="description">
<div><p>Given an integer <code>num</code>, return <em>the number of steps to reduce it to zero</em>.</p>

<p>In one step, if the current number is even, you have to divide it by <code>2</code>, otherwise, you have to subtract <code>1</code> from it.</p>

<p>&nbsp;</p>
<p><strong>Example 1:</strong></p>

<pre><strong>Input:</strong> num = 14
<strong>Output:</strong> 6
<strong>Explanation:</strong>&nbsp;
Step 1) 14 is even; divide by 2 and obtain 7.&nbsp;
Step 2) 7 is odd; subtract 1 and obtain 6.
Step 3) 6 is even; divide by 2 and obtain 3.&nbsp;
Step 4) 3 is odd; subtract 1 and obtain 2.&nbsp;
Step 5) 2 is even; divide by 2 and obtain 1.&nbsp;
Step 6) 1 is odd; subtract 1 and obtain 0.
</pre>

<p><strong>Example 2:</strong></p>

<pre><strong>Input:</strong> num = 8
<strong>Output:</strong> 4
<strong>Explanation:</strong>&nbsp;
Step 1) 8 is even; divide by 2 and obtain 4.&nbsp;
Step 2) 4 is even; divide by 2 and obtain 2.&nbsp;
Step 3) 2 is even; divide by 2 and obtain 1.&nbsp;
Step 4) 1 is odd; subtract 1 and obtain 0.
</pre>

<p><strong>Example 3:</strong></p>

<pre><strong>Input:</strong> num = 123
<strong>Output:</strong> 12
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>0 &lt;= num &lt;= 10<sup>6</sup></code></li>
</ul>
</div>
</div>

## Solution(Python)
```Python
class Solution:
    def numberOfSteps(self, num: int) -> int:
        cnt = 0
        while num:
            if num & 1:
                num -= 1
            else:
                num //= 2
            cnt += 1
        return cnt

```