5. Celender in java

import java.util.Scanner;
public class Celender {

 
    public static void main(String[] args) {
        int day,month,year;
        System.out.println("NOTE : Enter between 1600 to 2099 date.It is necessary. Otherwise unexpected error will occor.");
        System.out.println("Enter the date in DD/MM/YYYY form : ");
        Scanner sc=new Scanner(System.in);
        day=sc.nextInt();
        month=sc.nextInt();
        year=sc.nextInt();
        int l2d=year%100,result;
        result=day+l2d+(l2d/4);
        int mc=monthCode(month);
        int yc=yearCode(year);
        if(mc==-1||yc==-1)
            System.out.println("Somthing went wrong! Please try again.");
        else{
        result=result+mc+yc;
        result=result%7;
        dayCode(result);
        }
     }
   static int yearCode(int year)
    {
        if(year>=1600&&year<=1699)
            return 6;
        else if(year>=1700&&year<=1799)
            return 4;
        else if(year>=1800&&year<=1899)
            return 2;
        else if(year>=1900&&year<=1999)
            return 0;
        else if(year>=2000&&year<=2099)
            return 6;
        else
            return (-1);
    }
   static int monthCode(int month)
    {
        if(month==1||month==10)
            return 0;
        else if(month==2||month==3||month==11)
            return 3;
        else if(month==4||month==7)
            return 6;
        else if(month==5)
            return 1;
        else if(month==6)
            return 4;
        else if(month==8)
            return 2;
        else if(month==9||month==12)
            return 5;
        else
            return(-1);

    }
   static void dayCode(int day)
    {
        switch(day)
        {
            case 0:
                System.out.println("\nSunday");
                break;
            case 1:
                System.out.println("\nMonday");
                break;
            case 2:
                System.out.println("\nTuesday");
                break;
            case 3:
                System.out.println("\nWednesday");
                break;
            case 4:
                System.out.println("\nThursday");
                break;
            case 5:
                System.out.println("\nFriday");
                break;
            case 6:
                System.out.println("\nSaturday");
                break;
            default:
                System.out.println("\nSomthing went wrong! Please try again.");
        }
    }

}

Output:

4. Write a program to read 5 subjects marks of a student and calculate the total and grade

import java.util.*;  

 class Stud  

 {    

      public static void main(String args[])  

      {  

           Scanner in = new Scanner(System.in);  

           System.out.println("Student Records - 2013\n");  

           System.out.print("Name: ");  

           String name = in.nextLine();  

           System.out.print("USN: ");  

           String USN = in.nextLine();  

           System.out.println("Marks in 5 subjects: ");  

           int a[]=new int[5];  

           int tot=0;  

           boolean flag=false;  

           for(int i=0;i<5;i++)  

           {  

           System.out.print("Subject["+(i+1)+"]: ");  

                a[i] = in.nextInt();  

                if(a[i]<25)  

                {  

                     flag=true;  

                }  

                tot+=a[i];  

           }  

           float avg = tot/5;  

           System.out.println("Total: "+tot);  

           System.out.println("Percentage: "+avg+"%");  

           if(flag)  

           {  

                System.out.println("Status: FAIL");  

                return;  

           }   

           String grade="";  

           switch(Math.round(avg/10))  

           {  

                case 10:     grade="FCD";  

                case 9:      grade="FCD";  

                break;  

                case 8:      grade="FC";  

                case 7:      grade="FC";  

                break;       

                case 6 :     grade="SC";  

                case 4 :     grade="SC";  

                break;  

                case 3 :     grade="C";  

                break;  

                default :    grade="F";  

           }  

           System.out.println("Status: " +grade);  

      }  

 }  

Output:

3. Implement a Java program which prints the season name respective to its month number using if else and switch statements

import java.util.*;   
  public class IfElseDemo   
  {   
    public static void main(String args[])   
    {   
       System.out.print("Which Seasons: ");   
       Scanner in = new Scanner(System.in);   
       int month = in.nextInt();   
       String M=" ";   
       if(month==12||month==1||month==2)   
       M="Winter";   
       else if(month==3||month==4||month==5)   
       M="Spring";   
       else if(month==6||month==7||month==8)   
       M="Summer";   
       else if(month==9||month==10||month==11)   
       M="Autumn";   
       else if(month>12 ||month <1)   
       {   
         System.out.print("Invalid Entry");   
         return;   
       }   
               
             switch(M)  
             {       
                     case "Winter":  
                     System.out.print("Season: Winter");  
                     break;  
                       
                     case "Spring":  
                     System.out.print("Season: Spring");  
                     break;  
                       
                     case "Summer":  
                     System.out.print("Season: Summer");  
                     break;  
                       
                     case "Autumn":  
                     System.out.print("Season: Autumn");  
                     break;  
                       
             }   
    }   
  }   
   

Output:

2. Java program to implement Logical and Relational operators

class Operator  

  {  

    void LogicalOperator()   

    {  

       System.out.println("Logical Operator");  

       boolean x = true;  

       boolean y = false;  

       System.out.println("x & y : " + (x & y));  

       System.out.println("x && y : " + (x && y));  

       System.out.println("x | y : " + (x | y));  

       System.out.println("x || y: " + (x || y));  

       System.out.println("x ^ y : " + (x ^ y));  

       System.out.println("!x : " + (!x));  

    }  

      

    void RelationalOperator()  

    {   

       System.out.println("\nRelational Operator");  

    

       int x = 10, y = 5;  

       System.out.println("x > y : "+(x > y));  

       System.out.println("x < y : "+(x < y));  

       System.out.println("x >= y : "+(x >= y));  

       System.out.println("x <= y : "+(x <= y));  

       System.out.println("x == y : "+(x == y));  

       System.out.println("x != y : "+(x != y));  

   }   

      

    public static void main(String args[])  

    {  

       Operator o = new Operator();  

       o.LogicalOperator();  

       o.RelationalOperator();  

    }  

  }   

Output:

1. Simple java program to print "Hello World"

public class Hello  

 {  

   public static void main(String args[])  

      {  

     System.out.println("Hello world\n");  

     }  

 } 

Output:

.