JAVA SE Basic

Example of Java

import java.util.Scanner;
public class secondDegree {
     public static void main(String[] args){
             int a, b, c;
             double delta; // Declaration of variable
            
            Scanner input = new Scanner(System.in);

            Ssytem.out.println("Second Equation");
            System.out.println("Enter number of Axx:");
            a = input.nextInt();

           System.out.println("Enter number of Bx:");
           b = input.nextInt();

           System.out.println("Enter number of C:");
           c = input.nextInt();

           delta = (b*b) - 4(a*c);

           if(a + b + c == 0){
               System.out.println("x1 = 1  and " + "x2 = " + (c/a));
           }
           else if(a + c = b){
               System.out.println("x1 = -1 and " + "x2 = " + -(c/a));
            }
           else{
             if(delta < 0){
                 System.out.println("delta no Root!...");
             }
             else if(delta > 0){
                    System.out.println("x1 = " + (-b + (Math.sqrt(delat) ) / 2* a) );
                    System.out.println("x1 = " + ( -b - (Math.sqrt(delta)) / 2*a) );
             }
             else if(delta == 0){
                   System.out.println("Root is " + -b/(2*a));
             }
          }
     }
}

///////////////////////////////////////////Example Two//////////////////////////////////////////////

import java.util.Scanner;


public class Score {
    public static void main(String[] args){
       
        Scanner mysc = new Scanner(System.in);
       
        double avg = 0, score[], totalScore = 0;
        String grade = "";
        String username = "";
        String password = "";
        String[] subJect = {"Java", "PHP & MySQL", "Introduction to Programming", "HTML"};
        int i = 0;

        score = new double[subJect.length];
       
        System.out.println("User name:");
        username = mysc.next();
       
        System.out.println("Password:");
        password = mysc.next();
       
       
        for(i = 0; i < subJect.length; i++){
            System.out.println(subJect[i]);
            score[i] = mysc.nextDouble();
            totalScore += score[i];
        }
        avg = totalScore / subJect.length;
        if(avg >= 85 && avg <= 100){
             grade = "A";
        }else if (avg >= 75 && avg <= 84) {
            grade = "B";
        }else if (avg >= 65 && avg <= 74) {
            grade = "C";
        }else if (avg >= 50 && avg <= 64) {
            grade = "D";
        }else if (avg >= 0 && avg <= 49) {
            grade = "F";
        }else{
            grade = "Invalide Grade!";
        }
        System.out.println();
        System.out.println("...............................................");
        System.out.println("UserName is:" + username);
        System.out.println("Password is:" + password);
        for(i = 0; i < subJect.length; i++){
            System.out.println(subJect[i] + "=" + score[i]);
        }
        System.out.println("TotalScore is:" + totalScore);
        System.out.println("The Average is:" + avg);
        System.out.println("Grade is:" + grade);
    }
}