[leetcode]Pascal's Triangle II
2014-07-22 01:01
459 查看
Pascal's Triangle II
Given an index k, return the kth row of the Pascal's triangle.
For example, given k = 3,
Return
Note:
Could you optimize your algorithm to use only O(k) extra space?
算法：
思路1：
跟[leetcode]Pascal's Triangle 几乎一样，用2k个空间就可以搞定
思路2：
对空间进行优化，用k个空间搞定
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?
算法：
思路1：
跟[leetcode]Pascal's Triangle 几乎一样，用2k个空间就可以搞定
思路2：
对空间进行优化，用k个空间搞定
public List<Integer> getRow(int rowIndex) {
List<Integer> result = new ArrayList<Integer>();
if(rowIndex < 0) return result;
result.add(1);
for(int i = 1 ; i <= rowIndex;i++){
result = getNextRow(result);
}
return result;
}
private List<Integer> getNextRow(List<Integer> list){
int tem = 1;
for(int i = 1; i < list.size(); i++){
int a = list.get(i);
list.set(i, list.get(i) + tem);
tem = a;
}
list.add(1);
return list;
}
内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理 
相关文章推荐
- LeetCode(33)-Pascal's Triangle II
- 【leetcode】Pascal's Triangle II
- [LeetCode] Pascal's Triangle II 杨辉三角之二
- Pascal's Triangle II leetcode
- 【leetcode刷题笔记】Pascal's Triangle II
- [LeetCode 119] - 杨辉三角形II(Pascal's Triangle II)
- (leetcode)Pascal's Triangle II
- Leetcode: Pascal's Triangle II
- LeetCode——Pascal's Triangle II
- LeetCode:Pascal's Triangle I II
- [LeetCode] Pascal's Triangle II
- LeetCode（119） Pascal's Triangle II
- leetcode_119——Pascal's Triangle II （简单题，简单的递归）
- [leetcode]Pascal's Triangle II @ Python
- [LeetCode]Pascal's Triangle II
- [LeetCode] 119. Pascal's Triangle II 杨辉三角 II
- 学会从后往前遍历，例 [LeetCode] Pascal's Triangle II，剑指Offer 题4
- 【LeetCode】Pascal's Triangle II （杨辉三角）
- LeetCode-Pascal's Triangle II-帕斯卡三角-DP
- 【leetcode】Pascal's Triangle I & II （middle）