118. Pascal's Triangle 第一种解法:比较麻烦 https://leetcode.com/problems/pascals-triangle/discuss/166279/cpp-beats-1002018.9.3(with-annotation) class Solution { public: vector<vector<int>> generate(int numRows) { vector<vector<int>> result;…

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…

题目描述 给定一个非负整数 numRows,生成杨辉三角的前 numRows 行. 在杨辉三角中,每个数是它左上方和右上方的数的和. 示例: 输入: 5 输出: [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] 思路 对任意的n>0有 f(1, n)=1,(n>0) f(1, 2)=1,(n=2) f(i,j) = f(i-1, j-1)+f(i, j-1),i>2,j>2 代码实现 package Array; import java…

lc 118 Pascal's Triangle 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] ] DP Accepted 这个问题就是杨辉三角,先初始化边界,再用递推式ans[i][j] = ans[i…

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] ] 题目标签:Array 题目给了我们一个numRows,让我们写出这个行数的杨辉三角.来观察一下原题例子,5行的话,第一行只有1,第二行,只有1,第三行,除去第一个1和最后一个1,中间的都是上一行的两边…

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…

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 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: 观察法,JAVA实现如下: public List<List<Integer>> generate(int numRows) { List<List<Int…

杨辉三角,即组合数 递推 class Solution { vector<vector<int>> v; public: Solution() { ; i < ; ++i){ vector<,); ; j < i; ++j){ t[j] = v[i-][j] + v[i-][j - ]; } v.push_back(t); } } vector<vector<int>> generate(int numRows) { return vect…

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? 118. Pascal's Triangle 的拓展,给一个索引k,返回杨辉三角的第k行. 解法:题目要求优化到 O(k) 的空间复杂,那么就不能把每…

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…

[LeetCode]Pascal's Triangle II 解题报告 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/pascals-triangle-ii/description/ 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 yo…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)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] ] (二)解题…

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…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 Java解法 Python解法 日期 [LeetCode] 题目地址:https://leetcode.com/problems/pascals-triangle/ Total Accepted: 83023 Total Submissions: 247907 Difficulty: Easy 题目描述 Given a non-negative in…

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] ] Subscribe to see which companies asked this question [思路] 这道题目很简单,代码如下: public class Solution { publ…

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] ] 提示: 此题要求计算出给定行数的杨辉三角.只要摸清规律就并不难. 代码: class Solution { public: vector<vector<int> > genera…

Given a non-negative integer numRows, generate the first numRows of Pascal's triangle. In Pascal's triangle, each number is the sum of the two numbers directly above it. Example: Input: 5 Output: [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ] class…

Description Given a non-negative integer numRows, generate the first numRows of Pascal's triangle. In Pascal's triangle, each number is the sum of the two numbers directly above it. Example: Input: Output: [ [], [,], [,,], [,,,], [,,,,] ] 题目描述,给定一个数量…

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? 题目标签:Array 这道题目与之前那题不同的地方在于,之前是给我们一个行数n,让我们把这几行的全部写出来,这样就可以在每写新的一行的时候根据之前的那…

Given a non-negative index k where k ≤ 33, return the kth index row of the Pascal's triangle. Note that the row index starts from 0. In Pascal's triangle, each number is the sum of the two numbers directly above it. Example: Input: 3 Output: [1,3,3,1…

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 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…

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>>…

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>…

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…

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…

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]. 思路: 要求是返回帕斯卡某一行的数据 设置两个list变量,pre和next,pre用来存储当前的最后的最后一行,next存储下一行,next赋值给pre(在这之前pre清空,之后next清空),往下移动 - 代码: public class Solution { public…