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?
此题没什么好讲的，直接代码：
public class Solution {
public List<Integer> getRow(int rowIndex) {
List<Integer> res = new ArrayList<>();
for(int i=0;i<=rowIndex;i++){
res.add(0,1);
for(int j=1;j<res.size()-1;j++){
res.set(j,res.get(j)+res.get(j+1));
}
}
return res;
}
}