Question Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5,Return [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] Solution Key to the solution is to use two arrays, one for current list, one for previous a…

Question Given an index k, return the kth row of the Pascal's triangle. For example, given k = 3,Return [1,3,3,1]. Solution Similar with Pascal's Triangle. Note that the index starts from 0. public class Solution { public List<Integer> getRow(int ro…

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? 杨辉三角想必大家并不陌生,应该最早出现在初高中的数学中,其实就是二项式系数的一种写法. 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1…

Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5,Return [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] 杨辉三角是二项式系数的一种写法,如果熟悉杨辉三角的五个性质,那么很好生成,可参见我的上一篇博文: http://www.cnblogs.com/grandyang/p/4031536.html 具体生…

题目简述: 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? 解题思路: 这里的关键是空间的使用,既然只能用O(K)很容易就想到我们要进行回卷(名字好像不对).我的做法是每一次都在后面新加入一个数…

题目简述: Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5, Return [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1]] 解题思路: 很简单的问题,只要把两头的一拿出来,中间就是两个数相加了. class Solution: # @return a list of lists of integers def…

Problem: Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5,Return [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] Summary: 输出杨辉三角的前n行. Solution: 方法类似于LeetCode 119 Pascal's Triangle II class Solution { publ…

Problem: 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? Summary: 返回杨辉三角(帕斯卡三角)的第k行. Solution: 1. 若以二维数组的形式表示杨辉三角,则可轻易推算出ro…

题目: 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? 思路: 递归 package recursion; import java.util.List; import java.util.Arr…

Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5,Return [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] 思路:杨辉三角,直接按规律生成即可 vector<vector<int> > generate(int numRows) { vector<vector<int>>…