[求助]RAS加密算法求解
各位帮忙看看下面的RAS加密算法,,现求其解密的算法。
string ls_str
string sn = ""
ulong lul_temp
ulong lul_x
ulong lul_x0
ulong lul_x1
integer i
integer li_d
integer li_n
li_d = 7
li_n = 33
ls_str = trim(id) //id 为序列号
do until ls_str = ""
if left(ls_str,1) = "2" then
lul_temp = integer(mid(ls_str,2,2))
ls_str = right(ls_str,len(ls_str) - 3)
else
lul_temp = integer(mid(ls_str,2,1))
ls_str = right(ls_str,len(ls_str) - 2)
end if
lul_x0 = 1
lul_x1 = 1
for i = 1 to 4
lul_x0 = lul_x0 * lul_temp
next
lul_x0 = mod(lul_x0,33)
for i = 1 to li_d - 4
lul_x1 = lul_x1 * lul_temp
next
lul_x1 = mod(lul_x1,33)
lul_x = mod(lul_x0 * lul_x1,33)
sn = trim(sn) + string(lul_x)
loop