用户输入给出一系列答案

Question

我正在尝试创建一个短代码，允许用户提供输入，并根据输入显示数组。

我正在尝试显示坠落物体的速度和加速度。输入是间隔的数量，以及它们之间的时间。

我也遇到了int和double的问题.. 到目前为止我的代码，我觉得我没有进一步......：

package fall;
import java.util.Scanner;
public class fallSpeed {

    public static void main(String[] args) {

    Scanner input = new Scanner(System.in);
    System.out.print("Look at momentant(1), or interval (2):");
    int alternativ = input.nextInt();

    if (alternativ == 1) {

    System.out.print("Seconds of free fall:");

    int x;
    x = input.nextInt();

    double a = 9.81;
    double d;
    double v;

    v = x * a;
    d = 0.5 * v * x;
    if (x < 0) {
        System.out.println("Number must be over 0");
    }

    else{


    System.out.println("Distance:" + d + " " + "meter(s)");
    System.out.println("Speed after" + " " + x + " " + "sec.:" + v + " " + "m/s");
    }
    }

    if (alternativ == 2) { 

        System.out.print("Numbers of intervalls:");
        int ant = input.nextInt();
        System.out.print("Time between intervalls:");
        int step = input.nextInt();


            double [] a;
            //a.length;
            double [] v;
            double [] d;

            double[] obs= new double [ant];

            double[] speed;
            double[] acc;
            //double[] counter;

                for (ant=0;ant<=obs.length;ant++) 
                    int [] antall = [obs.length];

                    //int [] antall  = new int [ant];       
            //      array [counter] = (int) ant*step;
            //      
            //      fart = obs * a;
            //      array[acc] = (int) (speed* counter * 0.5);

                    System.out.print(ant);          
                    //for(int i=0;i<n;i++){//for reading array
                      //  arr[i]=s.nextInt();
        }
    }
}