13 problem solution such as trangle,circle,grade,vowel,small letter etc

package basicdata1;

import static java.lang.Math.sqrt;
import java.util.Scanner;


public class newFile {
     public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int digit;
        System.out.println("1.Determine Trangle");
        System.out.println("2.Determine Circle");
        System.out.println("3.Determine Even or Odd");
        System.out.println("4.Determine Positive or Negative or Zero");
        System.out.println("5.Determine Vowel Or Consonant");
        System.out.println("6.Determine Capital letter or Small letter");
        System.out.println("7.Determine large Number");
        System.out.println("8.Determine Grade");
        System.out.println("9.Determine Leap Year");
        System.out.println("10.Equilateral triangle Area");
        System.out.println("11.Isosceles triangle Area");
        System.out.println("12.Scalene triangle Area");
        System.out.println("13.Determine GPA  ");



        System.out.print("Enter your digit: ");
        digit = input.nextInt();


        switch(digit)
                {
            case 1:
                System.out.println("------------------------Please Follow This Step------------------------");
                double b,h, result;

        System.out.print("Enter your base : ");
        b = input.nextDouble();
        System.out.print("Enter your Height : ");
        h = input.nextDouble();

        result = 0.5 * b * h ;

        System.out.println("Area of a trangle : " +result);
                break;
            case 2:
                System.out.println("------------------------Please Follow This Step------------------------");
                double r, result1;

        System.out.print("Enter your Range : ");
        r = input.nextDouble();


        result1 = 3.1416 * r * r ;

        System.out.println("Area of a Circle : " +result1);
                break;
            case 3:
                System.out.println("------------------------Please Follow This Step------------------------");
                 double i;

        System.out.print("Enter your Number : ");
        i = input.nextDouble();


        if(i%2 == 0)
        {
          System.out.println("Even Number");
        }

        else
        {
            System.out.println("Odd Number");
        }
                break;
            case 4:
                System.out.println("------------------------Please Follow This Step------------------------");
                  double k;

        System.out.print("Enter your Number : ");
        k = input.nextDouble();


        if(k>0)
        {
          System.out.println("Positive Number");
        }

        else if(k<0)
        {
            System.out.println("Negative Number");
        }
        else
        {
         System.out.println("Zero");
        }
                break;
            case 5:
                System.out.println("------------------------Please Follow This Step------------------------");
                 char ch;

        System.out.print("Enter your Character : ");
        ch = input.next().charAt(0);


        if(ch == 'a'|| ch == 'e' || ch == 'i' || ch == 'o'|| ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O'  || ch == 'U')
        {
          System.out.println("Vowel");
        }


        else
        {
         System.out.println("Consonant");
        }
                break;
            case 6:
                System.out.println("------------------------Please Follow This Step------------------------");
                char ch1;

        System.out.print("Enter your Character : ");
        ch1 = input.next().charAt(0);


        if(ch1>='a' && ch1<='z')
        {
          System.out.println("Small letter");
        }


        else
        {
         System.out.println("Capital letter");
        }
                break;
            case 7:
                System.out.println("------------------------Please Follow This Step------------------------");
                 int num1,num2,large;
        System.out.print("Enter Two numbers : ");
        num1 =  input.nextInt();
        num2 =  input.nextInt();

        large = (num1>num2)?num1:num2;
        System.out.println("Large number is : " +large);
                break;
            case 8:
                System.out.println("------------------------Please Follow This Step------------------------");

                    double a1;

        System.out.print("Enter your Marks : ");
        a1 = input.nextInt();


      if(a1>=80)
      {
         System.out.println("You got A+");
      }
      else if(a1<80 && a1>=70)
      {
         System.out.println("You got A");
      }
       else if(a1<70 && a1>=60)
      {
         System.out.println("You got A-");
      }

      else if(a1<60 && a1>=50)
      {
         System.out.println("You got B");
      }

       else if(a1<50 && a1>=40)
      {
         System.out.println("You got C");
      }

        else if(a1<40 && a1>=33)
      {
         System.out.println("You got D");
      }

        else
        {

         System.out.println("You are Fail");
        }
                break;
            case 9:
                System.out.println("------------------------Please Follow This Step------------------------");
                int a2;

        System.out.print("Enter your Year : ");
        a2 = input.nextInt();


      if(a2%400 == 0 || a2%4 == 0 && a2%100 != 0)
      {
         System.out.println("Leap Year");
      }
      else
        {

         System.out.println("Not a leap Year");
        }
                break;

            case 10:
                System.out.println("--------------------Please follow this steps-----------------------");
                double a3,result4;

        System.out.print("Enter your length : ");
        a3 = input.nextDouble();

        result4 = 0.433012701 * a3 * a3;



         System.out.println("Equilateral triangle area : " +result4);
                break;

            case 11:
                System.out.println("--------------------Please follow this steps-----------------------");

               double a7,a8,result6;
        System.out.print("Enter your Same length: ");
        a7 = input.nextDouble();

        System.out.print("Enter your Another length: ");
        a8 = input.nextDouble();




        result6 = (a8 / 4) * sqrt( 4 *a7 * a7 -  a8 * a8);



         System.out.println("Isosceles triangle Area : " +result6);
                break;


                case 12:
                System.out.println("--------------------Please follow this steps-----------------------");

                double a4,a5,a6,s,result5;

        System.out.print("Enter your First length: ");
        a4 = input.nextDouble();

        System.out.print("Enter your Second length: ");
        a5 = input.nextDouble();

        System.out.print("Enter your Third length: ");
        a6 = input.nextDouble();

        s = (a4 + a5 + a6)/2;
        result5 = (sqrt(s * (s - a4) * (s - a5) * (s - a6)));



         System.out.println(" Scalene triangle area : " +result5);
                break;

                case 13:
                System.out.println("-----------Please Follow This Step-----------------------");
                double b1,b2,b3,b4,b5,b6,result9;
        System.out.println(" A+ ------ 5");
        System.out.println(" A  ------ 4");
        System.out.println(" A- ------ 3.75");
        System.out.println(" B  ------ 3");
        System.out.println(" C  ------ 2");
        System.out.println(" D  ------ 1");

        System.out.print("Enter Bangla Subject Point : ");
        b1 = input.nextInt();

        System.out.print("Enter English Subject Point : ");
        b2 = input.nextInt();

        System.out.print("Enter Math Subject Point : ");
        b3 = input.nextInt();

        System.out.print("Enter Science Subject Point : ");
        b4 = input.nextInt();

        System.out.print("Enter Information Tecnology Subject Point : ");
        b5 = input.nextInt();

        System.out.print("Enter Global Studies Subject Point : ");
        b6 = input.nextInt();

        result9 = (b1 + b2 + b3 + b4 + b5 + b6)/6;

        System.out.println("You got GPA : " +result9);
        break;


    }
            default:
                 System.out.println("Not a letter");
                break;


        }
    }
}