https://leetcode-cn.com/problems/minimum-path-sum/
Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right, which minimizes the sum of all numbers along its path.
Note: You can only move either down or right at any point in time.
Example 1:
Input: grid = [[1,3,1],[1,5,1],[4,2,1]] Output: 7 Explanation: Because the path 1 → 3 → 1 → 1 → 1 minimizes the sum. Example 2:
Input: grid = [[1,2,3],[4,5,6]] Output: 12
Constraints:
m == grid.length n == grid[i].length 1 <= m, n <= 200 0 <= grid[i][j] <= 100