Given an index k, return the kth row of the Pascal's triangle.

For example, given k = 3,

Return [1,3,3,1].

Note:

Could you optimize your algorithm to use only O(k) extra space?

class Solution {

public:

    vector<int> getRow(int rowIndex) {

        // Start typing your C/C++ solution below

        // DO NOT write int main() function

       vector<int> result(rowIndex+);

       result[] = ;

        int temp1 = , temp2 = ;

        for(int i = ; i<= rowIndex ; i++)

          for(int j = ; j< i+; j++){

            temp2 = result[j];

            if(j ==  || j == i)

                result[j] = ;

             else

                 result[j] += temp1 ;

            temp1 = temp2;

          }

          return result;

    }

};