LeetCode: Unique Paths II

一次过了

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int m = obstacleGrid.size();
        if (!m) return 0;
        int n = obstacleGrid[0].size();
        vector<vector<int>> f(m+1, vector<int>(n+1, 0));
        f[0][1] = 1, f[1][0] = 1;
        for (int i = 1; i <= m; i++) {
            f[i][1] = obstacleGrid[i-1][0] == 1? 0 : f[i-1][1];
        }
        for (int i = 1; i <= n; i++) {
            f[1][i] = obstacleGrid[0][i-1] == 1? 0 : f[1][i-1];
        }
        for (int i = 2; i <= m; i++) {
            for (int j = 2; j <= n; j++) {
                f[i][j] = obstacleGrid[i-1][j-1] == 1? 0 : f[i-1][j] + f[i][j-1];
            }
        }
        return f[m][n];
    }
};

 C#

public class Solution {
    public int UniquePathsWithObstacles(int[,] obstacleGrid) {
        int m = obstacleGrid.GetLength(0);
        int n = obstacleGrid.GetLength(1);
        if (m == 0 || n == 0) return 0;
        int[,] f = new int[m+1, n+1];
        f[0, 1] = f[1, 0] = 1;
        for (int i = 1; i <= m; i++) {
            f[i, 1] = obstacleGrid[i-1, 0] == 1? 0 : f[i-1, 1];
        }
        for (int i = 1; i <= n; i++) {
            f[1, i] = obstacleGrid[0, i-1] == 1? 0 : f[1, i-1];
        }
        for (int i = 2; i <= m; i++) {
            for (int j = 2; j <= n; j++) {
                f[i, j] = obstacleGrid[i-1, j-1] == 1? 0 : f[i-1, j] + f[i, j-1];
            }
        }
        return f[m, n];
    }
}