program Gxp1; var i , n , jr , jw , jb : integer ; ch1 : char ; ch : array[1..20] of char ; begin readln(n); for i:=1 to n do read(ch[i]); jr:=1; jw:=n; jb:=n; while (jr<=jw) do begin if (ch[jw]=’R’) then begin ch1:=ch[jr]; ch[jr]:=ch[jw]; ch[jw]:=ch1; jr:=jr+1; end else if ch[jw]=’W’ then jw:=jw-1; else begin ch1:=ch[jw]; ch[jw]:=ch[jb]; ch[jb]:=ch1; jw:=jw-1; jb:=jb-1; end end; for i:=1 to n do write(ch[1]); writeln; end.输入：10 RBRBWWRBBR输出：
