Given an indexk, return thekthrow of the Pascal's triangle. For example, givenk= 3, Return[1,3,3,1]. Note: Could you optimize your algorithm to use onlyO(k) extra space? 思路: the mth element of the nth row of the Pascal's triangle is C(n, m) = n!/(m! * (n-m)!) ...
Given an indexk, return thekthrow of the Pascal's triangle. For example, givenk= 3, Return[1,3,3,1]. Note: Could you optimize your algorithm to use onlyO(k) extra space? 解题思路: 因为计算杨辉三角时,仅仅用到相邻的两行的数据,所以我们能够反向计算,就能以O(k) 的时间复杂度解决这个问...
给定一个整数 rowIndex ,返回杨辉三角的第rowIndex 行。 在杨辉三角中,每一个数是它左上方和右上方的数之和。 进阶:使用空间复杂度为O(n) 的方法。 数据限制 1 <= rowIndex <= 33 样例 思路:DP 本题是 LeetCode 118 这题的加强版,需要将空间复杂度优化为 O(n) 。 空间复杂度为 O(n ^ 2) 的方...
LeetCode——Pascal's Triangle II Given an indexk, return thekthrow of the Pascal's triangle. For example, givenk= 3, Return[1,3,3,1]. Note: Could you optimize your algorithm to use onlyO(k) extra space? 原题链接:https://oj.leetcode.com/problems/pascals-triangle-ii/ 题目:给定一...
Pascal’s Triangle 题目大意 输出帕斯卡三角前N行 1 121 1331 解题思路 注意帕斯卡三角中,除了首尾,其他值为上一层的两个邻值的和 代码 class Solution(object): def generate(self, numRows): """ :type numRows: int :rtype: List[List[int]] ...
(numRows==2)returnresult;int[]number=newint[numRows];number[0]=1;number[1]=1;for(inti=3;i<=numRows;i++){int[]newNumber=newint[numRows];newList=newArrayList<Integer>();for(intj=0;j<i;j++){if(j==0){newList.add(1);newNumber[j]=1;}elseif(j==i-1){newList.add(1);new...
116 Pascal's Triangle.py 117 Populating Next Right Pointers in Each Node II.py 118 Populating Next Right Pointers in Each Node.py 119 Pascal's Triangle II.py 120 Triangle.py 121 Best Time to Buy and Sell Stock II.py 122 Best Time to Buy and Sell Stock.py 123 Best Time to...
升级版本,注意 Pascal's Triangle, 其实是左右是对称的. 在子函数pascal不用全部都遍历计算,只用处理len/2,其他用对称就可以 vector<int>pascal(vector<int>&nums,intline){vector<int>rows(line+1);intlen=nums.size();rows[0]=1;for(inti=1;i<=len/2;++i){rows[i]=nums[i-1]+nums[i];rows[le...
【leetcode】Pascal's Triangle II 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......
leetcode 118[easy]---Pascal's Triangle 难度:easy Given numRows, generate the first numRows of Pascal's triangle. For example, given numRows = 5, Return 思路:帕斯卡三角形。每层的每个元素就是上一行两个相邻元素相加(第一个和最后一个元素是1)。用两个for循环实现。......