preamble numVariables 4 numConstraints 4 relations OneInThree end
OneInThree(x1 x2 x3)
OneInThree(x1 x2 x4)
OneInThree(x1 x3 x4)
OneInThree(!x2 !x3 !x4)

preamble numVariables 4 numConstraints 3 relations Or end
Or(a !b c !d) 3
Or(a b !c) 4
Or(!a) 100

// c = true
preamble numVariables 2 numConstraints 3 relations Or end
sat 3
Or(a b) 4
Or(!a) 100

// in addition a = true
preamble numVariables 2 numConstraints 3 relations Or end
sat 3
sat 4
unsat 100