思路:基础动态规划方程,啥都不说了,直接上代码。
code:
class Solution {
public:
int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
vector<vector<int>> ret(obstacleGrid.size(),vector<int>(obstacleGrid[0].size()));
ret[0][0] = obstacleGrid[0][0] == 1? 0:1;
for(int j = 1;j < obstacleGrid[0].size();j++)
ret[0][j] = obstacleGrid[0][j] == 1 ? 0 : ret[0][j-1];
for(int i = 1;i < obstacleGrid.size();i++)
ret[i][0] = obstacleGrid[i][0] == 1 ? 0 : ret[i-1][0];
for(int i = 1;i < obstacleGrid.size();i++)
for(int j = 1;j< obstacleGrid[0].size();j++)
ret[i][j] = obstacleGrid[i][j] == 1? 0 : ret[i-1][j] + ret[i][j-1];
return ret[obstacleGrid.size()-1][obstacleGrid[0].size()-1];
}
};