Ivan Kazmenko:
arr.map !(to !(string)) .join (" ") .writeln;
I suggest to not put a space before the bang (!), because it's confusing for me.
Also, "arr.map !(to !(string))" is better written "arr.map!text".But even better is to use the range formatting of writefln, avoiding the "map", "to", and "join", something like:
writefln("%(%d %)", arr); Bye, bearophile