leetcode124，Leetcode: Pascal's Triangle II

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?

分析：細節實現題。代碼如下：

class Solution {
public:vector<int> getRow(int rowIndex) {if(rowIndex == 0) return vector<int>(1,1);vector<int> result(2,1);for(int i = 3; i <= rowIndex+1; i++){vector<int> next;next.push_back(1);for(int j = 1; j < i-1; j++){next.push_back(result[j-1] + result[j]);}next.push_back(1);result = next;}return result;}
};

leetcode124，?