How should I practice Minimum Cost to Remove Stones?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Airbnb online assessment problems in FastPrep.

Is Minimum Cost to Remove Stones associated with Airbnb?

FastPrep tags this as a Airbnb online assessment coding practice problem when the problem catalog has that company and stage context.

Minimum Cost to Remove Stones

Airbnb● HardFULLTIMEOA

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Problem statement

There are n stones in a row, indexed from 0 to n - 1. Stone i has two associated costs: oneNeighborCost[i] and twoNeighborCost[i].

Remove every stone in any order. At the moment stone i is removed, its cost is:

twoNeighborCost[i] if both immediately adjacent stones i - 1 and i + 1 still exist.
oneNeighborCost[i] if exactly one of those immediately adjacent stones still exists.
0 if neither immediately adjacent stone still exists.

An index outside the row does not contain a stone. Return the minimum possible total cost of removing all stones.

Function

minimumRemovalCost(oneNeighborCost: int[], twoNeighborCost: int[]) → long

Examples

Example 1

oneNeighborCost = [3,4,5]twoNeighborCost = [10,1,10]return = 1

Remove stone 1 first for cost 1. Its removal leaves both end stones without an immediate neighbor, so both are then removed for free.

Example 2

oneNeighborCost = [1,10,1]twoNeighborCost = [5,1,5]return = 1

Remove the middle stone first for cost 1. Both end stones are then isolated and can be removed for free.

Constraints

1 <= n <= 5 * 10^4.
oneNeighborCost.length == twoNeighborCost.length == n.
1 <= oneNeighborCost[i], twoNeighborCost[i] <= 1000.