How should I practice Validate Linked List Pointer Ordering?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Bloomberg LP phone screen problems in FastPrep.

Is Validate Linked List Pointer Ordering associated with Bloomberg LP?

FastPrep tags this as a Bloomberg LP phone screen coding practice problem when the problem catalog has that company and stage context.

Validate Linked List Pointer Ordering

Bloomberg LP● MediumNEW GRADPHONE SCREEN

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Problem statement

Arrays encode one singly linked list: next[i] is the next node index and head its first node. Every node is visited exactly once. Auxiliary backward[i] and forward[i] are node indices or -1 for null.

Return true if every non-null backward pointer targets an earlier list position and every non-null forward pointer targets a later position.

Function

validPointerOrder(next: int[], backward: int[], forward: int[], head: int) → boolean

Examples

Example 1

next = [1,2,-1]backward = [-1,0,0]forward = [2,2,-1]head = 0return = true

All auxiliary pointers point in their required list direction.

Constraints

All arrays have equal length.
All nonnegative indices are valid.