s:=(c:=File standardInput contents)slice(7) if(c>"e",write(s clone removeOddIndexes,s removeEvenIndexes reverse),t:=s slice(c=1006)reverse s=s slice(0,c) c repeat(i,write(s slice(i,i+1),t slice(i,i+1))))
Note that non-ascii characters in the above source code will be escaped (such as \x9f).