const as integer NUMOPS = 4
const as integer N = 4

dim as zstring ptr optab(0 to NUMOPS - 1) = {@"+", @"-", @"*", @"/"}
dim as integer dat(0 to N - 1) = {1, 2, 3, 4}

dim as integer cnt = (N ^ N) * (NUMOPS ^ (N - 1))
dim as integer l = (N * 2) - 1

dim as integer values(0 to l - 1)

print "cnt: " & cnt
print "l  : " & l

for i as integer = 0 to cnt - 1
	dim as integer temp = i
	dim as string expr
	dim as integer bad_flag
	for j as integer = 0 to l - 1
		if (j and 1) = 0 then
			' must be a number
			values(j) = temp mod N
			temp \= N
			expr &= dat(values(j))
		else
			' must be an operator
			values(j) = temp mod NUMOPS
			temp \= NUMOPS
			expr &= *optab(values(j))
		end if
		' If we are not at the first number, and we are at a number,
		' look back and make sure this number hasn't appeared before.
		if j and ((j and 1) = 0) then
			for k as integer = j - 2 to 0 step - 2
				if values(j) = values(k) then
					bad_flag = 1
					exit for
				end if
			next k
		end if
	next j
	if bad_flag = 0 then
		print expr
	end if
next i