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? class Solution { public: vector<int> getRow(int rowIndex) { // Start typ…

Triangle Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below. For example, given the following triangle [ [], [,4], [6,,7], [4,,8,3] ] The minimum path sum from top to bottom is…

118 - Pascal's Triangle 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: class Solution { public: vector<vector<int>> generate(int n…

一.Pascal's Triangle 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] ] class Solution { public: vector<vector<int>> generate(int numRows) { vect…

杨辉三角形II(Pascal's Triangle II) 问题 给出一个索引k,返回杨辉三角形的第k行. 例如,给出k = 3,返回[1, 3, 3, 1] 注意: 你可以优化你的算法使之只使用O(k)的额外空间吗? 初始思路 首先来复习复习杨辉三角形的性质(来自wiki): 杨辉三角以正整数构成,数字左右对称,每行由1开始逐渐变大,然后变小,回到1. 第行的数字个数为个. 第行的第个数字为组合数. 第行数字和为. 除每行最左侧与最右侧的数字以外,每个数字等于它的左上方与右上方两个数字之和(也…

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] 我们为了满足空间复杂度的要求,我们新建两个ArrayList,一个负责存储上一个Pascal行的结果,一个根据上一个Pascal行得出当前P…

原文题目: 118. Pascal's Triangle 119. Pascal's Triangle II 读题: 杨辉三角问题 '''118''' class Solution(object): def generate(self, numRows): """ :type numRows: int :rtype: List[List[int]] """ if not numRows: return [] result = [] for i i…

Pascal's Triangle II Total Accepted: 19384 Total Submissions: 63446 My Submissions Question SolutionGiven 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 us…

当我们需要改变数组的值时,如果从前往后遍历,有时会带来很多麻烦,比如需要插入值,导致数组平移,或者新的值覆盖了旧有的值,但旧有的值依然需要被使用.这种情况下,有时仅仅改变一下数组的遍历方向,就会避免这些困难. 最直观的一题是 剑指Offer上的面试题 4 另外一道例题,就是LeetCode上的 Pascal's Triangle II Pascal's Triangle II Given an index k, return the kth row of the Pascal's triangl…

Pascal's Triangle 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] ] class Solution: # @return a list of lists of integers def generate(self, numRows):…