【动态规划】不同路径Ⅱ

题目链接：https://leetcode.cn/problems/unique-paths-ii/description/

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int>>& obstacleGrid) 
    {
        int m = obstacleGrid.size(), n = obstacleGrid[0].size();
        // 1. 创建 dp 表
        vector<vector<int>> dp(m + 1, vector<int>(n + 1));
        // 2. 初始化
        dp[1][0] = 1;
        // 3. 填表
        for (int i = 1; i <= m; ++i)
            for (int j = 1; j <= n; ++j)
                if (obstacleGrid[i - 1][j - 1] == 0)
                    dp[i][j] = dp[i][j - 1] + dp[i - 1][j];
        // 4. 返回值
        return dp[m][n];
    }
};