<p>How to convert last 3 digits of number into 0</p>

<p>example 3444678 to 3444000</p>

<p>I can do like </p>

<p>(int)(3444678/1000) * 1000= 3444000</p>

<p>But division and multiplication could be costly...</p>

<p>Any other solution????</p>

You could try
```
```
n - (n % 1000)
```
```
but the modulus operator might be as costly as a division. In any case, this sounds an awful lot like a micro-optimization. Is this really your bottleneck?