Java foundation 2-----loop structure

import java.util.Random;  
import java.util.Scanner;  
/**
 * Chapter 4 Loop Structure
 * @author Administrator
 *
 */  
  
public class Text1 {  
    public static void main(String[] args) {  
        /*
         * repeat output i love you
         * int i=0;
        for(i=0;i<=10;i++){
            System.out.println("I love you"+i);
        }*/  
  
  
  
        / * 1 + 2 + 3 .... 100 sum
        int i=0;
        int sum=0;
        while (i<=100) {
            sum=sum+i;
            i++;
        }
        System.out.println("====sum===="+sum);*/  
  
  
  
        /* Find the average score of the college
        Scanner scanner=new Scanner(System.in);
        System.out.println("Please enter the total number of students: ");
        int person=scanner.nextInt();
        int i=1;
        int sum=0;
        while (i<=person) {
            System.out.println("Please input "+i+" student's grade: ");
            int a =scanner.nextInt();
            sum=sum+a;
            i++;
        }
        System.out.println("The average grade of the student is: ==========="+sum/person);*/  
  
  
        /*
         * int year=2006;
        int sum = 80000;
        while (sum<=200000) {
            sum=(int) (sum+sum*0.25);  
            year++;
        }
        System.out.println("==============="+year);*/  
  
  
  
  
        /* random number comparison size
        Scanner scanner=new Scanner(System.in);
        Random random=new Random();
        int a=random.nextInt(101);
        int number;
        do{
            System.out.println("Please enter a number and compare the size with the number from the computer: ");
            number=scanner.nextInt();
            if(number<a){
                System.out.println("smaller");
            }else if(number>a){
                System.out.println("big");    
            }
 
        }while(number!=a);
 
        System.out.println("Congratulations on your answer");*/     
  
        /* System.out.println("Please enter a number: ");
        Scanner scanner=new  Scanner(System.in);
        int number=scanner.nextInt();
        for(int i=0,j=number;i<=j;i++,j--){
            System.err.println(i+"+"+j+"="+(i+j));
        }*/  
  
        /*
        int i=1;
        while(i<=7){
            System.out.println("Baby feeding: "+i+" times");  
            int j=1;
            while (j<=3) {
                System.out.println("喂奶："+j+"次");
                j++;
            }
            i++;
        }
         */  
  
  
        /*
         * Ninety-nine multiplication table
         * for(int i=1;i<=9;i++){
            for(int j=1;j<=i;j++){
                System.out.print(j+"*"+i+"="+j*i+"\t");
            }
            System.out.println();
        }*/  
  
  
        /*
                //How many days are there from 1990 to May 7, 2016.
        int sum=0;
        for(int year=1900;year<=2016;year++){
            if(year%4==0 && year%100!=0||year%400==0){
                sum=sum+366;
            }else{
                sum=sum+365;
            }
        }
        for(int month=1;month<=5;month++){
            if(month==2){
                if(2017%4==0 && 2017%100!=0||2017%400==0){
                    sum=sum+29;
                }else{
                    sum=sum+28;
                }
            }else{
                if(month==4||month==6||month==9||month==11){
                    sum=sum+30;  
                }else{
                    sum=sum+31;  
                }
            }
 
        }
        System.out.println("How many days in total"+(sum+7));
        sum+=22;
        int wekday=sum%7;
        System.out.println("Day\tone\ttwo\tthree\tfour\tfive\tsix");
         for(int i=1;i<=wekday;i++){
             System.out.print("\t");
         }
 
         for(int i=1;i<=30;i++){
            if(sum%7==6){
                 System.out.print(i+"\n");
            }else{
                 System.out.print(i+"\t");
            }
            sum++;
         }
         */  
  
  
  
  
        /**
         * How many days from 1990 to June 22, 2017
         */  
        /*System.out.println("Please enter the year");
        Scanner scanner=new Scanner(System.in);
        int year=scanner.nextInt();
        System.out.println("Please enter the month");
        int month=scanner.nextInt();
 
        int sum=0;
        for(int i=1990;i<year;i++){
            if(i%4==0 && i%100!=0 ||i%400==0){
                sum=sum+366;
            }else{
                sum=sum+365;
            }
        }
 
        for(int i=1;i<month;i++){
            if(i==2){
                if(year%4==0 && year%100!=0 ||year%400==0){
                    sum=sum+29;
                }else{
                    sum=sum+28;
                }
            }else{
                if(i==4||i==6||i==9||i==11){
                    sum=sum+30;
                }else{
                    sum=sum+31;  
                }
            }
 
        }
        sum=sum+28;
        System.out.println("How many days in total"+(sum));
        System.out.println("Day\tone\ttwo\tthree\tfour\tfive\tsix");
        int weakey=sum%7;
        for(int i=1;i<=weakey;i++){
            System.out.print("\t");
        }
 
        for(int i=1;i<=31;i++){
            if(sum%7==6){
                System.out.print(i+"\n");
            }else{
                System.out.print(i+"\t");    
            }
            sum++;
        }*/  
  
  
  
    }   
}