(phixonline)-->
constant tbl = sq_add(1,{{0, 3, 1, 7, 5, 9, 8, 6, 4, 2},
{7, 0, 9, 2, 1, 5, 4, 8, 6, 3},
{4, 2, 0, 6, 8, 7, 1, 3, 5, 9},
{1, 7, 5, 0, 9, 8, 3, 4, 2, 6},
{6, 1, 2, 3, 0, 4, 5, 9, 7, 8},
{3, 6, 7, 4, 2, 0, 9, 5, 8, 1},
{5, 8, 6, 9, 7, 2, 0, 1, 3, 4},
{8, 9, 4, 5, 3, 6, 2, 0, 1, 7},
{9, 4, 3, 8, 6, 1, 7, 2, 0, 5},
{2, 5, 8, 1, 4, 3, 6, 7, 9, 0}})
function damm(string s)
integer interim = 1
for i=1 to length(s) do
integer nxt = s[i]-'0'+1
if nxt<1 or nxt>10 then return 0 end if
interim = tbl[interim][nxt]
end for
return interim == 1
end function
constant tests = {"5724", "5727", "112946", "112949"}
for i=1 to length(tests) do
string ti = tests[i]
printf(1,"%7s is %svalid\n",{ti,iff(damm(ti)?"":"in")})
end for