
1) Constraint programming
Found on
https://www.crosswordclues.com/clue/backjumping

This fact can be exploited by collecting, in each node, a set of previously assigned variables whose evaluation suffices to prove that no solution exists in the subtree rooted at the node. This set is built during the execution of the algorithm. When retracting from a node, this set is removed the variable of the node and collected in the set of t...
Found on
http://en.wikipedia.org/wiki/Backjumping
No exact match found.