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ID3 decision tree algorithm background knowledge ID3 algorithm was first proposed by J. Ross Quinlan at the University of Sydney in 1975. The core of the algorithm is "information entropy". By calculating the information gain of each attribute, ID3 algorithm considers that the attribute with high information gain is a good attr ...

The time complexity and space complexity of common sorting algorithms are as follows: 1. Algorithm efficiency There are two kinds of algorithm efficiency analysis: The first is time efficiency and the second is space efficiency. Time efficiency is called time complexity, and space efficiency is called space complexity. Time complexity mainly ...

catalogue188. The best time to buy and sell stocks IVsubjectProblem solution 188. The best time to buy and sell stocks IV subject Given an array of integers   prices, its i-th element   prices[i] is the price of a given stock on day I. Design an algorithm to calculate the maximum profit you can make. You can complete up to k transacti ...

subject A two-dimensional grid map grid of row x col is given, where grid[i][j] = 1 represents land and grid[i][j] = 0 represents water. The grids in the grid are connected horizontally and vertically (not diagonally). The whole grid is completely surrounded by water, but there happens to be an island (or an island connected by one or more gri ...

Classic interview questions of binary tree Before that, I have published the basic knowledge of binary tree: Detailed explanation of binary tree Next, I will tell you some classic and common binary tree interview questions Preliminary interview questions Maximum depth of binary tree Question: Maximum depth of binary tree Solution idea: ...

2.1 linear regression algorithm model representation Let's start with an example: this example is to predict housing prices. We want to use a data set containing housing prices in Portland, Oregon. Here, I want to draw my data set according to the selling prices of different house sizes. For example, if your friend's house is 1250 square feet ...

Polynomial evaluation For polynomials f ( x ) = a 0 + a ...

    Today, let's learn more about Vision Transformer. timm based code. 1. Patch Embedding Transformer was originally used to do NLP work, so ViT's primary task is to convert the graph into word structure. The method adopted here is to divide the picture into small blocks, as shown in the lower left corner of the above figure. Eac ...

subject Give you a matrix board of m x n, which consists of several characters' X 'and' O ', find all areas surrounded by' X ', and fill all' O 'in these areas with' X '. Example 1 Input: board = [["X","X","X","X"],["X","O","O","X"],["X","X","O","X"],["X","O","X","X"]] Output:[["X","X","X","X"],["X","X","X","X"],["X","X","X","X"],["X","O","X ...

1, Basic introduction 1. Basic introduction Hash table (also known as hash table) is a data structure that is accessed directly according to the Key value. In other words, it accesses records by mapping key values to a position in the table to speed up the search. This mapping function is called hash function, and the array storing records is ...