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>>…

题目: 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] ] 代码: 仔细一看,规律就是本层第一个和最后一个的元素都是1,其他的元素分别等于上一层同位置元素加上前一个位置的元素. 一百度,才知道,这就是大名鼎鼎的杨辉三角!只可惜,在欧洲,这个表叫做帕斯…

题目来源 https://leetcode.com/problems/pascals-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]. 题意分析 Input:integer Output:kth row of the Pascal's triangle Conditions:只返回第n行 题目思路 同118,不…