Advanced Programming-Week7

Summary

1. 字符串
   1. 拼接
   2. charAt()

Task50

package Task50;
import javax.swing.*;
import java.util.*;

public class Task50{
    public static void main(String []args)
    {
        int a;
        Scanner in = new Scanner(System.in);
        a=in.nextInt();
        if(a<1||a>9)
        {
            System.out.println("The number you input is error.");
        }else {
            for(int i=0;i<a;i++)
            {
                for(int j=0;j<=i;j++)
                {
                    System.out.print(j+1);
                }
                System.out.println();
            }
            System.out.println();
            for(int i=a;i>0;i--)
            {
                int t=a;
                for(int j=0;j<i;j++)
                {
                    System.out.print(t--);
                }
                System.out.println();
            }
        }
    }
}

Task51

package Task51;

import java.util.Scanner;

public class Task51 {
    public static void main(String []args)
    {
        int rows,columns;
        char use;
        Scanner in = new Scanner(System.in);
        System.out.printf("Enter number of rows:\t\t");
        rows=in.nextInt();
        if(rows<1||rows>25)
        {
            System.out.printf("The rows you enter is not a right number.");
        }
        System.out.printf("Enter number of columns:\t");
        columns=in.nextInt();
        if(columns<1||columns>25)
        {
            System.out.printf("The columns you enter is not a right number.");
        }
        System.out.printf("Enter symbol of use:\t\t");
        in.nextLine();
        String t=in.nextLine();
        use=t.charAt(0);
        for(int i=0;i<rows;i++)
        {
            for(int j=0;j<columns;j++)
            {
                System.out.print(use);
            }
            System.out.println();
        }
    }
}

Task52

import java.util.*;

public class Task52{
    public static void main(String []args)
    {
        for(int i=1;i<=100;i++)
        {
            String ans=""+i;
            if(i%3==0)
            {
                ans="Fizz";
            }
            if(i%5==0)
            {
                if(ans.equals("Fizz"))
                ans+="Buzz";
                else ans="Buzz";
            }
            if(i%5!=0)
            System.out.printf(ans+"\t");
            else
            System.out.println(ans+"\t");
        }
    }
}

Task53

package Task53;

import java.util.Scanner;

public class Task53 {
    public static void main(String []args)
    {
        int n;
        Scanner in = new Scanner(System.in);
        n=in.nextInt();
        int n1=n;
        int n2=0;
        while(n!=0)
        {
            n2*=10;
            n2+=n%10;
            n/=10;
        }
        if(n1==n2){
            System.out.println("The number is a palindromic number.");
        }else 
        System.out.println("The number is not a palindromic number.");
    }
}

Task54

package Task54;

import java.util.*;
import javax.swing.*;

public class Task54 {
    public static void main(String []args)
    {
        String menuMessage;
        double pi = 3.14,sideLength,base,height,area;
        menuMessage = "Choose an option from the following menu:";
        menuMessage += "\n1. Calculate area of circle";
        menuMessage += "\n2. Calculate area of square";
        menuMessage += "\n3. Calculate area of triangle";
        String option = JOptionPane . showInputDialog (null , menuMessage) ;
        System.out.println(option);
        if (option.equals("1")) 
        {
            double radius = Double.parseDouble(JOptionPane.showInputDialog(null,"Enter radius:"));
            area = pi*radius*radius;
            JOptionPane.showMessageDialog(null, "The area is" + area) ;
        }
        else if (option.equals("2"))
        {
            sideLength = Double.parseDouble (JOptionPane . showInputDialog (null, "Enter length of a side"));
            area = sideLength*sideLength;
            JOptionPane.showMessageDialog (null,"The area is"+ area) ;
        }
        else if (option.equals("3"))
        {
            base = Double.parseDouble (JOptionPane .showInputDialog(null, "Enter base length"));
            height = Double.parseDouble (JOptionPane .showInputDialog(null, "Enter height length"));
            area = base*height*0.5;
            JOptionPane.showMessageDialog(null, "The area is"+ area) ;
        }
        else
            JOptionPane.showMessageDialog(null, "Hit any key to try again");
        
    }
}

Task55

package Task55;

import java.util.Random;

public class Task55 {
    public static void main(String []args)
    {
        Random random = new Random();
        int []a = new int[7];
        for(int i=0;i<600;i++)
        {
            int f=random.nextInt(6)+1;
            a[f]++;
        }
        System.out.println("Face\tFrequency");
        for(int i=0;i<6;i++){
            System.out.println(i+1+"\t"+a[i+1]);
        }
    }
}

Task56

package Task56;

public class Task56 {
    public static void main(String []args)
    {
        int salary1=0;
        int salary2=0;
        for(int i=1;i<=10;i++)
        {
            salary1+=100;
        }
        int basic=1;
        for(int i=1;i<=10;i++)
        {
            salary2+=basic;
            basic*=2;
        }
        System.out.println("The option1 is "+ salary1);
        System.out.println("The option1 is "+ salary2);
    }
}

Task58

package Task58;

import java.util.*;

public class Task58 {
    public static void main(String []args)
    {
        int a;
        Scanner in= new Scanner(System.in);
        a=in.nextInt();
        if(a<5||a>9)
        {
            System.out.println("The range you enter is error.");
        }else{
            for(int i=0;i<a;i++)
            {
                for(int j=a;j>i;j--)
                {
                    System.out.print(j);
                }
                System.out.println();
            }
            System.out.println();
            for(int i=1;i<=a;i++){
                for(int j=1;j<=i;j++){
                    System.out.print(j);
                }
                System.out.println();
            }
        }
    }
}

Task59

package Task59;

import java.util.*;

import javax.swing.JOptionPane;

public class Task59 {
    public static void main(String []args)
    {
        int []a=new int[7];
        int num;
        num=Integer.parseInt(JOptionPane.showInputDialog(null,"How many random notes would you like \n(input must be in the range 1 to 50)?"));
        Random random=new Random();
        for(int i=0;i<num;i++)
        {
            int t;
            t=random.nextInt(7);
            a[t]++;
        }
        String message="Count of each note is as follows:";
        for(int i=0;i<7;i++){
            message+="\n"+(char)(i+'A')+":"+a[i];
        }
        JOptionPane.showMessageDialog(null,message);
    }
}