state 1, unmodified first 12 points: signs [1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1] -> accepted
state 1, sixth point deleted:        signs [1, -1, 1, -1, 1, 1, -1, 1, -1, 1, -1] -> rejected
state 1, with the points of state 2:  signs [1, 1, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1] -> rejected
state 1, two points interchanged:    signs [1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1] -> rejected
state 2, unmodified first 12 points: signs [1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1] -> accepted
state 2, sixth point deleted:        signs [1, -1, 1, -1, 1, 1, -1, 1, -1, 1, -1] -> rejected
state 2, with the points of state 1:  signs [-1, -1, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1] -> rejected
state 2, two points interchanged:    signs [1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1] -> rejected
selftest: unmodified prefixes accepted and all corruptions rejected
