s:=" "repeated(n:=File standardInput readLine asNumber);for(i,0,n*2-1,writeln(d:=(s .. c:="RGB".. s)slice(i,i+n),c slice(i,i+1)repeated(n*2),d asMutable reverse rstrip))
Note that non-ascii characters in the above source code will be escaped (such as \x9f).