with(combinat):
Help:=proc(): print(`redu(L)`):end:

#redu(L): the reduction of the list L of distinct numbers. Try:
#redu([4,1,3]);
redu:=proc(L) local i,n,L1,T:
n:=nops(L):
L1:=sort(L):
for i from 1 to n do
 T[L1[i]]:=i:
od:
[seq(T[L[i]],i=1..n)]:
end: