Difficulty with the backtracking algorithm about classiccomputerscienceproblemsinjava HOT 1 CLOSED

unassigned represents the next unused variable to explore the domain of. The possible values for its domain are explored in the for-loop that follows it. If it turns out no domain values end up fulfilling the constraints, we will return null (after the for-loop, meaning we have explored all possible domain values) and backtrack to a prior assignment.

I assumed you were asking about unassigned. If you are asking about v in the closure, it just represents all of the variables, one at a time, until we find one that is not in the current assignment.

Hope this helps.

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