Module Dinesman_s_multiple_dwelling_problem {
	// this is the standard perimutation function
	// which create a lambda function:
	// pointer_to_array=Func(&BooleanVariable)
	// when BooleanVariable = true we get the last permutation
	Function PermutationStep (a as array) {
		c1=lambda (&f, a) ->{
			=a : f=true
		}
		integer m=len(a)
		if m=0 then Error "No items to make permutations"
		c=c1
		While m>1
			c1=lambda c2=c,p=0%, m=(,) (&f, a, clear as boolean=false) ->{
				if clear then m=(,)
				if len(m)=0 then m=a
				=cons(car(m),c2(&f, cdr(m)))
				if f then f=false:p++:  m=cons(cdr(m), car(m)) : if p=len(m) then p=0 : m=(,):: f=true
				}
			c=c1
			m--
		End While
		=lambda c, a (&f, clear as boolean=false) -> {
			=c(&f, a, clear)
		}
	}
	boolean k
	object s=("Baker", "Cooper", "Fletcher", "Miller", "Smith")
	StepA=PermutationStep(s)
	while not k
		s=StepA(&k)
		if s#val$(4)= "Baker" then continue
		if s#val$(0)="Cooper" then continue
		if s#val$(0)="Fletcher" then continue
		if s#val$(4)="Fletcher" then continue
		if s#pos("Cooper")> s#pos("Miller") then continue
		if abs(s#pos("Smith")-s#pos("Fletcher"))=1 then continue
		if abs(s#pos("Cooper")-s#pos("Fletcher"))=1 then continue
		exit  // for one solution
	end while
	object c=each(s)
	while c
		Print array$(c)+" lives on floor "+(c^+1)
	end while
}
Dinesman_s_multiple_dwelling_problem