Prepare for the interview and stick to the third sentence of the question - Branch sentences!

This column 『 Hundred days and hundred questions 』 Long term renewal , Join this question brushing plan , Grow up together ！

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Preface

How to brush questions ？

Some students just like it , It's the ultimate difficulty , I feel that as long as I make the most difficult , The rest is easily solved . This kind of eager thought should not .

Algorithm training is a systematic project , need Step by step , Too eager for quick success and instant benefit , Instead, it is easy to feel frustrated because you can't solve problems , Counterproductive .

I remember one of my colleagues did something similar . I just heard about Cattle from , Just want to try it , After he went up, he picked a difficult topic , As a result, I thought for a long time and didn't do it , Get yourself particularly depressed .

You will find that this practice is inefficient , Even if the problem is solved , It doesn't mean you can solve other problems .

The reasonable way is to go step by step .

My suggestion is to brush the basic grammar questions first , Lay a good foundation and further brush algorithm problems , In this way, first of all, the basic grammar and common API There is absolutely no problem , It will definitely get twice the result with half the effort when brushing algorithm problems later !

This column will take you from basic grammar to advanced algorithms , Keep practicing step by step , Join the question brushing plan and come on ！

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Here I recommend Cattle from If you are confident in the basic grammar of the corresponding language, you can also brush algorithm problems , Here, the difficulty classification of algorithm problems on niuke.com is also great , There are introductory questions , Interview must brush questions , Interview high-frequency questions and so on . If the foundation is poor, then don't worry , Cattle from There are also basic grammar questions above to help you better learn the basics .

In order to make it convenient to brush the questions, I put the link of Niuke directly below , You can click the blue font to jump and brush the questions directly ！

Portal ： Brush the entry

This column will take you from basic grammar to advanced algorithms , Keep practicing step by step , Join the question brushing plan and come on ！

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JAVA5 Calculate the mall discount 【 Branch 】

subject ：

Answer key ：

import java.util.*;

public class Main {
    
    public static void main(String[] args) {
    
        Scanner console = new Scanner(System.in);
        int price = console.nextInt();
        int cost = 0;

        //write your code here......
        if(price>=5000){
    
            cost = (int)(price*0.6);
        }else if(price>=2000){
    
            cost = (int)(price*0.7);
        }else if(price>=500){
    
            cost = (int)(price*0.8);
        }else if(price>=100){
    
            cost = (int)(price*0.9);
        }else{
    
            cost = (int)price;
        }

        System.out.println(cost);
    }
}

JAVA6 Judge body mass index 【 Branch 】

subject ：

Answer key ：

import java.util.Scanner;

public class Main {
    
	public static void main(String[] args) {
    
	    Scanner scanner = new Scanner(System.in);
	    double height = scanner.nextDouble();
	    double weight = scanner.nextDouble();
	    //write your code here......
	    double log = weight/(height*height);
	    if(log<18.5){
    
	        System.out.println(" Thin ");
	    }else if(log>=18.5 && log<20.9){
    
	        System.out.println(" slim ");
	    }else if(log>=20.9 && log<24.9){
    
	        System.out.println(" Moderate ");
	    }else{
    
	        System.out.println(" Overweight ");
	    }
	}
}

JAVA7 Judge the grades of students 【 Branch 】

subject ：

Answer key ：

import java.util.Scanner;

public class Main {
    
    public static void main(String[] args) {
    
        Scanner scanner = new Scanner(System.in);
        String grade =scanner.next();

        //write your code here......
        if(grade.equals("A"))// This question mainly examines == and equals The difference between , If you use ==, This will return to false
            //== Are the addresses compared equal , Or whether the basic types are equal ; and grade yes new Coming out , It's an address 
            // Used to point to new Out object , So it belongs to the reference type 
            // about String class ,equals It's rewritten , Compare the content, not the address 
            System.out.println(" good ");
        else if(grade.equals("B"))
            System.out.println(" good ");
        else if(grade.equals("C"))
            System.out.println(" pass ");
        else if(grade.equals("D"))
            System.out.println(" fail, ");
        else
            System.out.println(" Unknown level ");
    }
}

JAVA8 Mailbox validation 【 Branch 】

subject ：

Answer key ：

import java.util.Scanner;

public class Main {
    
    public static void main(String[] args) {
    
        Scanner scanner = new Scanner(System.in);
        String str = scanner.next();
        String emailMatcher="[a-zA-Z0-9][email protected][a-zA-Z0-9]+\\.[a-zA-Z0-9]+";
        // utilize matches() Method for regular matching , If the legitimate , The output " The email format is legal ", Otherwise output " The email format is illegal "
        if(str.matches(emailMatcher)){
    
	        System.out.print(" The email format is legal ");
        }else{
    
	        System.out.print(" The email format is illegal ");
	    }
    }
}

Regular expression related knowledge points ：

// Modifier + Indicates that at least one of the characters is matched 
// Modifier ? Indicates that zero or one of the characters can be matched 
//A-z Action is equal to the a-zA-Z
// \d Match the Numbers 0-9
// \D Match not 0-9
// \w Match the letter 、 Numbers 、 Underline , Except for special characters and spaces 
// {n,m} Match at least n Time , at most m Time 
// ^ Flag indicating the beginning of string matching 
//  For more regular expression matching, see ：https://www.runoob.com/java/java-regular-expressions.html

Conclusion

In order to make it convenient to brush questions, I put the link of the website directly below , You can click the blue font to jump and brush the questions directly ！

Portal ： Brush Title artifact

Brush the question , Everyone must be serious , Don't slack off ！

Accumulate over a long period , Fang Chengda ！