import random class Solution(object): def __init__(self, nums): """ :type nums: List[int] """ self.data = {} for index, num in enumerate(nums): self.data.setdefault(num, []).append(index) def pick(self, target): """ :type target: int :rtype: int """ indexes = self....
每次Pick的时间复杂度是O(1)。C++代码如下:class Solution { public: Solution(vector<int> nums) { for (int i = 0; i < nums.size(); ++i) { m_[nums[i]].push_back(i); } } int pick(int target) { auto v = m_[target]; int s = v.size(); int i = rand() % s; return ...
importrandom string="helloworld"index=random.randrange(0,len(string))selected_char=string[index]print("选取的字符为:",selected_char) 1. 2. 3. 4. 5. 6. 7. 执行以上代码,每次都会输出一个随机选取的字符。 4. 类图 根据提供的信息,我们可以使用Mermaid语法绘制以下类图: RandomStringPicker+pick_rando...
return seq[int(self.random() * len(seq))] # raises IndexError if seq is empty def shuffle(self, x, random=None): """x, random=random.random -> shuffle list x in place; return None. Optional arg random is a 0-argument function returning a random float in [0.0, 1.0); by default...
下面是实现"Python List Random Pick"的步骤: 现在让我们逐步进行每个步骤的代码实现,并解释每一行代码的用途。 步骤1:导入random模块 首先,我们需要导入Python的random模块来使用其中的函数。可以使用以下代码导入random模块: importrandom 1. 步骤2:创建一个包含元素的列表 ...
random模块 2019-11-22 14:51 − random模块是用于取随机数的模块,常用方法如下: random,uniform取随机小数 : 数学计算 1 import random 2 print(random.random()) # 取0-1之间的小数 3 #结果:0.25640490341052324 4 print(random.u... YJ-TX 0 323 LeetCode 398. Random Pick Index 2019-12-11...
So the starting point is, again, to import that module, random. 让我们考虑一个简单的例子,其中列表中包含一组数字,我们希望从这些数字中随机统一选择一个。 Let’s think about a simple example where we have a set of numbers contained in a list,and we would like to pick one of those numbers...
LeetCode 398. Random Pick Index 2019-12-11 09:25 − 原题链接在这里:https://leetcode.com/problems/random-pick-index/ 题目: Given an array of integers with possible duplicates, randomly output the index of a given... Dylan_Java_NYC 0 477 ...
始，并且会在上边显示姓名变化，再点按钮，点名结束，最后显示的姓名即为结果import xlrd import random import tkinter as tk class NamePicker:def __init__(self, excel_file):读取excel数据 self.names = []workbook = xlrd.open_workbook(excel_file)worksheet = workbook.sheet_by_index(0)for...
def createRoute(cityList): route = random.sample(cityList, len(cityList)) return route 重复运行createRoute函数,直到我们有了足够的个体: def initialPopulation(popSize, cityList): population = [] for i in range(0, popSize): population.append(createRoute(cityList)) return population 确定适应度...