A piece of cryptographic function

Functions | Cryptographic function MIS (prestring)
Dim texts
Dim seed
Dim I,length
prestring = Trim (prestring)
length = Len (prestring)
Seed = length
Texts = ""
For i = 1 to length
seed = Int (94*rnd (-ASC (mid prestring,i,1)-seed*asc (right (prestring,1))) +32)
Texts = texts & Chr (SEED) & Chr (int (94*rnd (-seed) +32))
Next
Dim dist
Dist= ""
For i = 1 to len (texts)
If ASC (Mid (texts,i,1)) >64 and ASC (Mid (texts,i,1)) <123 Then
Dist=dist+mid (texts,i,1)
End If
Next
MIS = dist
End Function