Unique Paths II （dp题）

Follow up for "Unique Paths":

Now consider if some obstacles are added to the grids. How many unique paths would there be?

An obstacle and empty space is marked as 1 and 0 respectively in the grid.

For example,

There is one obstacle in the middle of a 3x3 grid as illustrated below.

[
  [0,0,0],
  [0,1,0],
  [0,0,0]
]

The total number of unique paths is 2.

Note: m and n will be at most 100.

代码：

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
          if(obstacleGrid.size()==) return ;
          int row=obstacleGrid.size();
          int col=obstacleGrid[].size();
          int dp[][];
          memset(dp,,sizeof(dp));
          bool rblockTag=false;
          bool cblockTag=false;
          if(obstacleGrid[][]==||obstacleGrid[row-][col-]==)
            return ;
          for(int i=;i<col;++i){
              if(obstacleGrid[][i]==) rblockTag=true;
              if(!rblockTag) dp[][i]=;
              else dp[][i]=;
          }
          for(int j=;j<row;++j){
              if(obstacleGrid[j][]==) cblockTag=true;
              if(!cblockTag) dp[j][]=;
              else dp[j][]=;
          }
          for(int i=;i<row;++i){
              for(int j=;j<col;++j){
                  if(obstacleGrid[i][j]==) dp[i][j]=;
                  else dp[i][j]=dp[i][j-]+dp[i-][j];//i和j是从1开始
              }
          }
          return dp[row-][col-];
      }
};