such that cannot be extended to form a solution with whatever
value for . If the algorithm can prove this fact, it can
directly consider a different value for instead of reconsidering
as it would normally do. | | |- || An example in which the
current assignment to has been unsuccessfully tried with every
possible value of . Backtracking goes back to , trying to assign
it a new value. || Instead of backtracking, the algorithm makes
some further elaboration, proving that the evaluations , , and
are not part of any solution. || As a result, the current
evaluation of is not part of any solution, and the algorithm can
directly backjump to , trying a new value for it. | The
efficiency of a backjumping algorithm depends on how high it is
able to backjump. Ideally, the algorithm could jump from to
whichever variable is such that the current assignment to cannot
be extended to form a solution with any value of . If this is
the case, is called a safe jump. Establishing whether a jump is
safe is not always feasible, as