How to loop character A-Z in SAS?

To loop characters A-Z elegantly, we can have two ways as follows:

data _null_;
    put "First method:";
    string = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'; * string from A to Z;
    do i=1 to length(string);
        char = substrn(string, i, 1);
        put char=; 
    end;

    put "Second method (using RANK and BYTE):";
    do i=rank('A') to rank('Z');
        char = byte(i);
        put char=;
    end;
run;

If you can find any way better, please let me know.