Return the complete number

[a11e99z]

On Wednesday, 24 July 2019 at 15:45:08 UTC, Greatsam4sure wrote:
> int main(){
>  double mum = 0;
>  Write("enter a number: ")
>  readf(" %s\n",&num);
>  Writeln(num);
>
> }
>
> How do I return the complete number the user enter since I 
> don't since the user can enter numbers of various length with 
> dmd approximating it.
>
> I will appreciate any help

as drug said: writefln with formatting
in case no need prints just string representation use
   s/format https://dlang.org/phobos/std_format.html#format
auto str = num.format!"%.16s"; // using UFCS
or
auto str = "%.16s".format( num); // UFCS too for 2nd version of 
format
or
string str = format( "%.16s", num);

simple help can be asked on IRC channel too 
irc://irc.freenode.net/d
(HexChat, mIRC clients and others)