How to remove all characters from a string, except the integers?

[matheus]

On Friday, 4 March 2022 at 21:20:20 UTC, Stanislav Blinov wrote:
> On Friday, 4 March 2022 at 19:51:44 UTC, matheus wrote:
>
>> OK but there is another problem, I tested your version and 
>> mine and there is a HUGE difference in speed:
>
>>     string s, str = "4A0B1de!2C9~6";
>
>> Unless I did something wrong (If anything please tell). By the 
>> way on DMD was worse, it was like 5x slower in your version.
>
> To add to the already-mentioned difference in allocation 
> strategies, try replacing the input with e.g. a command-line 
> argument. Looping over a literal may be skewing the results.

Interesting and I'll try that way. Thanks.

Matheus.