Programmer Group

Palindrome linked list Create a stack, store all the data in the linked list in the stack, and then compare the data in the stack with all the data in the linked list. Using the single step pointer and the double step pointer, when the two-step pointer finally reaches the end of the list, the second ...

Inverse Document Frequency (IDF for short) If a certain word is less, but it appears many times in this article, it may reflect the characteristics of this article, which is the key words we need Word frequency (TF) = the number of times a word appears in an article / the number of times a word app ...

Python 3 natural language processing (5) - preprocessing Note: please contact the blogger, or pay attention to the WeChat public number "citation space". Otherwise, the plagiarism will be reported! 1. participle When a document or a long string needs to be processed, the first thing you need ...

1, Structure The structure is similar to the class in java, but it only has properties and no methods 1.1 define, declare, initialize structure, access structure members #include <stdio.h> #define SIZE 20 //Defining structure struct book { char name[SIZE]; char author[SIZE]; double price; ...

This is a good tool for R to play machine learning. Install the rattle() package &gt; install.packages("rattle") &gt; library(rattle) Rattle: A free graphical interface for data science with R. XXXX 5.3.0 Copyright (c) 2006-2018 Togaware Pty Ltd. //Type 'rattle()' to flick, wiggle, and tumble your data. Rattler, you're too naughty Ru ...

The core point of the underlying implementation of ArrayList 1. The collection bottom layer is implemented by using array 2. Why can a set store infinite size? ####The implementation of array expansion technology Arrays.copyOf: To copy the array, return the copied array. Parameters are the copied arr ...

Title Source: https://atcoder.jp/contests/abc153 Winter vacation was so decadent that I didn't write a question all the time. Then I almost mistook the second question. And the last question at that time, I would not But if I make up the difference and learn some skills, I will score up if I play that g ...

The types of questions about strings in question library are as follows String, character array, integer conversion, etc Rule judgement Digital operation Related to Array Operations dynamic programming Advanced data structure 1. Conversion of string, character array, integ ...

Structured process design The principle of structured programming can be expressed as: program = (algorithm) + (data structure). The three basic structures of structured programming are sequence structure, selection structure and cycle structure. Sequential structure Sequential structure means that ...

(1) Database creation 1) Database classification System database and user database; distinguish database type by viewing object Explorer; Note: the master database should not be moved. This is the database of the database. We mainly study the user database; 2) User database file composition T ...