[Leetcode从零开刷]119. Pascal's Triangle II
2018-02-28 10:11
477 查看
题目来源
leetcode题目要求:
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?
题目解答:
这个和(18. Pascal’s Triangle)题目一样,最傻逼的办法就是用这个代码,返回最后一个就行,但是空间超了,也可以accepted·class Solution { public List<Integer> getRow(int rowIndex) { List<List<Integer>> res = new ArrayList<>(); List<Integer> row,pre = null; for(int i=0;i<=rowIndex;i++){ row = new ArrayList<>(); for(int j=0;j<=i;j++){ if(j==0||j==i) row.add(1); else row.add(pre.get(j-1)+pre.get(j)); } pre = row; res.add(row); } return res.get(res.size()-1); } }
厉害的c++
class Solution { public: vector<int> getRow(int rowIndex) { vector<int> A(rowIndex+1, 0); A[0] = 1; for(int i=1; i<rowIndex+1; i++) for(int j=i; j>=1; j--) A[j] += A[j-1]; return A; } };
相关文章推荐
- LeetCode 119. Pascal's Triangle II
- 119. Pascal's Triangle II LeetCode
- [LeetCode][119. Pascal's Triangle II][easy]Java实现,杨辉三角
- LeetCode 119. Pascal's Triangle II
- LeetCode 119. Pascal’s Triangle II
- Leetcode 119 Pascal's Triangle II
- LeetCode-119:Pascal's Triangle II (返回杨辉三角指定行)
- LeetCode119——Pascal's Triangle II
- LeetCode119. Pascal's Triangle II-python(easy)
- 【LeetCode】119.Pascal's Triangle II(Easy)解题报告
- leetcode:119 Pascal's Triangle II-每日编程第二十五题
- LeetCode 119:Pascal's Triangle II
- leetcode 119 Pascal's Triangle II C++
- 119. Pascal's triangle II Leetcode Python
- [LeetCode] 119. Pascal's Triangle II
- 2017.11.14 LeetCode - 118. Pascal's Triangle - 119. Pascal's Triangle II
- leetcode 119. Pascal's Triangle II
- [Leetcode] 119. Pascal's Triangle II 解题报告
- 【LeetCode】119 Pascal's Triangle II
- LeetCode-Array-119. Pascal's Triangle II