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…

题目来源 https://leetcode.com/problems/pascals-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] ] 题意分析 Input:integer Output:帕斯卡三角 Conditions:帕斯卡三…

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…

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] ] 已知行数生成帕斯卡三角.实际上只要有第i层,那么就能生成第i+1层.每次新生成的层加入最终集合中即可. public List<List<Integer>…

LeetCode: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] ] 分析:简单的模拟从第一层开始计算即可 class Solution { public: vector<vector<int> > g…

118. 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) { vector<vector<…

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? 上一道题的延伸版,就是直接求出第k行的数,要求用o(k)的空间复杂度. 也是直接相加就可以了. public class Solution { pub…

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] ] 用的比价暴力的方法, 也是最快的. public class Solution { List list = new ArrayList<List<Integer>>(); public…

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] ]分析:此题其实就是表现出帕斯卡三角的特征:它是一个三角形矩阵,其顶端是 1,视为(row0).第1行(row1)(1&1)两个1,这两个1是由他们上头左右两数之和 (不在三角形内的数视为0).依此类推产…

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…

题目描述: Given an index k, return the kth row of the Pascal's triangle. For example, given k = 3,Return [1,3,3,1]. 解题思路: 每次在上一个list前面插入1,然后后面的每两个间相加赋值给前一个数. 代码描述: public class Solution { public List<Integer> getRow(int rowIndex) { List<Integer> r…

题目描述: 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: 每一行都是在前一行的基础上在第一个位置插上1,然后其余的部分两两相加得到新的值. 注意每次添加进母list中的子list必须新开辟空间,否则所有的子list全部指向相同的对象.…

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? public class Solution { public List<Integer> getRow(int rowIndex) { if(row…

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: ackage cn.magicdu; import java.util.ArrayList; import java.util.List; public class _118_Pa…

Given an index k, return the kth row of the Pascal's triangle. For example, given k = 3,Return [1,3,3,1]. 分析 二项式展开式的系数 不加(long long)提交会出错. class Solution { public: vector<int> getRow(int rowIndex) { vector<int> vals; vals.resize(rowIndex+); va…

1.题目描述 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? 2.解法分析 题目说要优化空间需求,实际上就是要复用空间,于是写出的代码如下: class Solution { publi…

题目是: 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? (注意:这里要求空间为O(k)) 一个满足条件的答案如下: public class Solution { public IList<int…

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? 这道题倒是不难,有个有意思的地方是可以优化到O(k)的空间复杂度.下面先上O(k^2)的算法. @Test public List<Integer>…

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] ] https://oj.leetcode.com/problems/pascals-triangle/ 杨辉三角,先把两遍的值设为1,然后算中间的就是上一层的两个数相加,算当前层的时候,上一层下标一定是…

问题 给出变量numRows,生成杨辉三角形的前numRows行. 例如,给出numRows＝5,返回: [     [1],    [1,1],   [1,2,1],  [1,3,3,1], [1,4,6,4,1]] 初始思路 基本算法和 杨辉三角形II(Pascal's Triangle II) 的基本一致.每算完一行的值将这些值拷贝一份到vector中即可.代码如下: class Solution { public: std::vector<std::vector<int> >…

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? vector<int> getRow(int rowIndex) { // Start typing your C/C++ solution b…