C# 二维dp 代码

public class Solution {
    public int MinPathSum(int[][] grid) {
        int n = grid.Length, m = grid[0].Length;
        int[][] dp = new int[n][];
        for (int i = 0; i < n; i++){
            dp[i] = new int[m];
            Array.Fill(dp[i], int.MaxValue);
        }

        dp[0][0] = grid[0][0];
        for (int i = 0; i < n; i++){
            for (int j = 0; j < m; j++){
                if (i > 0) dp[i][j] = Math.Min(dp[i][j], dp[i - 1][j] + grid[i][j]);
                if (j > 0) dp[i][j] = Math.Min(dp[i][j], dp[i][j - 1] + grid[i][j]);
            }
        }

        return dp[n - 1][m - 1];
    }
}

C# 一维dp 代码

public class Solution {
    public int MinPathSum(int[][] grid) {
        int n = grid.Length, m = grid[0].Length;
        int[] dp = new int[m];

        for (int i = 0; i < n; i++){
            for (int j = 0; j < m; j++){
                if (i == 0 && j == 0) dp[0] = grid[0][0];
                else if (j == 0) dp[j] = dp[j] + grid[i][j];
                else if (i == 0) dp[j] = dp[j - 1] + grid[i][j];
                else dp[j] = Math.Min(dp[j], dp[j - 1])+ grid[i][j];
            }
        }

        return dp[m - 1];
    }
}