"Leetcode" Unique Paths II

Unique Paths II

Follow up for "Unique Paths":

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

An obstacle and empty space are marked as and respectively in the 1 0 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 would be is at most 100.

With the above question difference is not big, only need to judge has the obstacle to place 0 can.

For the first row column, the first obstacle and the number of paths followed are 0

classSolution { Public:    intUniquepathswithobstacles (vector<vector<int> > &Obstaclegrid) {        if(Obstaclegrid.empty ())return 0; Else if(obstaclegrid[0].empty ())return 0; Else        {//m>=1, N>=1            intm =obstaclegrid.size (); intn = obstaclegrid[0].size (); Vector<vector<int> > Count (M, vector<int> (n,0));  for(inti =0; I < m; i + +)            {                if(obstaclegrid[i][0] ==0) count[i][0] =1; Else                     Break; }             for(intj =0; J < N; J + +)            {                if(obstaclegrid[0][J] = =0) count[0][J] =1; Else                     Break; }             for(inti =1; I < m; i + +)            {                 for(intj =1; J < N; J + +)                {                    if(Obstaclegrid[i][j] = =1) Count[i][j]=0; ElseCount[i][j]= count[i-1][j]+count[i][j-1]; }            }            returncount[m-1][n-1]; }    }};

"Leetcode" Unique Paths II