MediumNo. 2304

Minimum Path Cost in a Grid — LeetCode 2304 Python Solution

Topics
Array, Dynamic Programming, Matrix
Reading time
2 min

The problem

You are given a 0-indexed m x n integer matrix grid consisting of distinct integers from 0 to m * n - 1. You can move in this matrix from a cell to any other cell in the next row.

Example

Input
grid = [[5,3],[4,0],[2,1]], moveCost = [[9,8],[1,5],[10,12],[18,6],[2,4],[14,3]]
Output
17
Explanation
The path with the minimum possible cost is the path 5 -> 0 -> 1.

Python solution

PythonSolution
class Solution:
    def minPathCost(self, grid: List[List[int]], moveCost: List[List[int]]) -> int:
        m, n = len(grid), len(grid[0])
        f = grid[0]
        for i in range(1, m):
            g = [inf] * n
            for j in range(n):
                for k in range(n):
                    g[j] = min(g[j], f[k] + moveCost[grid[i - 1][k]][j] + grid[i][j])
            f = g
        return min(f)

Complexity

Time
O(m × n2)
Space · auxiliary
O(n)

Pattern: Matrix and Grid

Treat a 2-D grid as a graph whose neighbours are the four adjacent cells. LeetCode 2304. Minimum Path Cost in a Grid is filed here because LeetCode tags it Matrix, which is the vocabulary this hub collects.

The matrix and grid guide has the Python template for the pattern and the 216 LeetCode problems that use it.

Related problems

Related problems
No.ProblemDifficulty
0063Unique Paths IIMedium
0064Minimum Path SumMedium
0085Maximal RectangleHard
0174Dungeon GameHard
0221Maximal SquareMedium
0329Longest Increasing Path in a MatrixHard

Frequently asked questions

How hard is LeetCode 2304. Minimum Path Cost in a Grid?

LeetCode 2304. Minimum Path Cost in a Grid is rated Medium on LeetCode.

What is the time complexity of LeetCode 2304. Minimum Path Cost in a Grid?

The Python solution on this page runs in O(m × n2).

What is the space complexity of LeetCode 2304. Minimum Path Cost in a Grid?

The Python solution on this page uses O(n) auxiliary space.

What topics does LeetCode 2304. Minimum Path Cost in a Grid cover?

LeetCode 2304. Minimum Path Cost in a Grid is tagged Array, Dynamic Programming and Matrix on LeetCode.

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