constraint.txt
	-valid origional sample
constraint1.txt
	-invalid no file
constraint2.txt
	-valid fewer variables and values
constraint3.txt
	-unary contradiction
constraint4.txt
	-binary contradiction
constraint5.txt
	-binary unary contradiction
constraint6.txt
	-no solution
constraint7.txt
	-valid (no unary)
constraint8.txt 
	-valid (no binary)
constraint9.txt
	-valid (no unary or binary)
constraint10.txt
	-invalid empty def