ch20ex1: Not Done

import java.util.Scanner;

public class ch20ex1 {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);




        double x, wut = 0, c;

        double sum = 0, avg = 0, min = 0, max = 0, sd = 0, mode = 0;
        double med = 0;



        System.out.println("Enter the number of grades: ");
        x = scan.nextDouble();





        double[] grades = new double[x];


        for (int index = 0; index < x; index++) {
            wut = index + 1;
            System.out.println("Enter the grade for student " + wut + ": ");
            grades[index] = scan.nextInt();


        }

        System.out.println("What would you like to find? ");
        System.out.println("[1]= average");
        System.out.println("[2]= minimum");
        System.out.println("[3]= maximum");
        System.out.println("[4]= standard deviation");
        System.out.println("[5]= median");
        System.out.println("[6]= mode");
        System.out.println("[7]= exit");
        c = scan.nextInt();


        // Calculating the sum
        for (int index = 0; index < x; index++) {
            sum = sum + grades[index];
        }



        // Calculating avg
        if (c == 1) {
            avg = sum / x;
            System.out.println("Average: " + avg);      //   ***DELETE "for" LOOPS BELOW***
        }




        //Calculating min
        if (c == 2) {
            min = grades[0];
            for (int index = 0; index < grades.length; index++) {
                if (grades[index] < min) {
                    min = grades[index];

                }
            }
            System.out.println("Min: " + min);
        }



        //Calculating max
        if (c == 3) {
            max = grades[0];
            for (int index = 0; index < grades.length; index++) {
                if (grades[index] > max) {
                    max = grades[index];

                }
            }
            System.out.println("Max: " + max);

        }



        //Calculating sd
        for (int index = 0; index < x; index++) {       //Skipping sd for now
            if (c == 4) {
            }
        }

        //Calculating med
              //
            if (c == 5) {
                double o = 0, L = 0, k = 0, g = 0;
                for( int index = 0; index < grades.length; index++ ){
                    if( grades.length % 2 != 0){
                        L = grades.length - 1;
                        o = L / 2;
                        k = o + 1;
                        med = grades[o];

                    }
                    if( grades.length % 2 == 0 ){
                        L = grades.length / 2;
                        o = L + 1;
                        k = grades[L] + grades[o];
                        g = k / 2;
                        med = g;


                    }
                }
                System.out.println("Median: " + med);
            }


        //Calculating mode
        for (int index = 0; index < x; index++) {       //
            if (c == 6) {
            }
        }

        //Calculating exit thing
        if (c == 7) {
            System.out.println("Goodbye o/");
            System.exit(0);
        }





    }
}