How should I practice Minimum-Weight Path Through a Matrix?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Meta onsite interview problems in FastPrep.

Is Minimum-Weight Path Through a Matrix associated with Meta?

FastPrep tags this as a Meta onsite interview coding practice problem when the problem catalog has that company and stage context.

Minimum-Weight Path Through a Matrix

Meta● MediumFULLTIMEONSITE INTERVIEW

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Problem statement

Given a square matrix grid, find the minimum travel cost from its top-left cell to its bottom-right cell. A cell with value -1 is blocked. Every other value is the nonnegative cost of entering that cell.

You may move to any of the eight neighboring cells, including diagonals. The starting cell is not charged; every later entered cell contributes its value. Return the minimum total cost, or -1 if the destination cannot be reached.

Function

minimumWeightedPathCost(grid: int[][]) → int

Examples

Example 1

grid = [[0,5],[2,1]]return = 1

The diagonal enters the destination at cost 1; the starting cell is free.

Example 2

grid = [[0,9,9],[1,-1,1],[2,1,0]]return = 2

Move through the cost-1 cell at (1,0), then the cost-1 cell at (2,1), then the cost-0 destination.

Example 3

grid = [[0,-1,2],[-1,-1,1],[2,1,0]]return = -1

All three neighboring cells of the start are blocked, so no path reaches the destination.

Constraints

1 <= grid.length <= 50 and every row has exactly grid.length cells.
Each cell is -1 or an integer from 0 through 1000.
Costs are nonnegative, so revisiting a cell cannot improve a minimum-cost path.