Game array question

[janice91]

Dear experts,

I am trying to practice inheritance coding on my own but i have met some difficulties.

I ma supposed to come up with a Square Game with M representing the number of squares. For the start, i will be in the square 0 value and playing by throwing dice. There are 2 types of squares, Standard square (represented by 0) and Unique Square (represented by 1). Both have value attribute ( can be negative or positive), and Unique Square has one more attribute called multiplier. When land on Standard Square, i need to get points according to the 'value' of the square. When land on Unique Square, i need to multiply my current score with 'multiplier' first, then add 'value'. I am also required to out print my final score at the end.

I have figured out the algorithm, please kindly take a look at the image which i have attached in this thread.

Here's the sample input:
5
0 5.25
0 -3.14
1 2.17 1.50
0 5.39
1 -3.32 2.00
3 3 1 2

Here's the sample output which i was given:
Points: 7.77

import java.util.*;
import java.text.*;

class Game{

    public static int[] MakeArray (int size, int value){
        int [] Array = new int[size];
        for (int i = 0; i < Array.length; i++){
            Array[i] = value;
        }  return Array;
    }

    public static void main(String[] args){
        // declare the necessary variables
        int M, squaretype;
        double curPoints = 0;
        double multiplier, value;
        int[] arrayRef;

        // declare a Scanner object to read input
        Scanner sc = new Scanner(System.in);
        M = sc.nextInt();

        for (int i = 0; i < M; i++){
            squaretype = sc.nextInt();
            value = sc.nextDouble();
            multiplier = sc.nextDouble();
            arrayRef = MakeArray (M,value);
        } [B]// how should i continue?[/B]

        DecimalFormat twoDecimalFormat = new DecimalFormat("0.00"); // format to 2 decimal place
        System.out.println("Points: " + twoDecimalFormat.format(curPoints)); 
    }
}

class Square{

    double _value; // value which can be positive or negative

    public double getValue() {  
        return _value;
    }

    public double changePoints(double curPoints){
        return (curPoints + _value);
    }
}

class UniqueSquare extends Square{

    double _multiplier;

    public double getMultiplier (){
        return _multiplier;
    }

    public double changePoints(double curPoints){
        return((curPoints*_multiplier)+ _value);
    }
}

Thank you so much for all your kind guidance.

[JamesCherrill]

Maybe your array should be an array of Squares, not an array of ints?

[janice91]

Maybe your array should be an array of Squares, not an array of ints?

Thank you James for your suggestion.
Is the changes below which you suggested to change to;

public static Square[] MakeArray (int size, int value){
        square [] Array = new square[size];
        for (int i = 0; i < Array.length; i++){
            Array[i] = value;
        }  return Array;
    }

so that i can declare a

Square[] squares = new Square[M];

in my main method?

[JamesCherrill]

Basically, yes. Try it.

[janice91]

Basically, yes. Try it.

I have tried what you have mentioned, but i received a compilation error when trying to compile the program. It stated that it's incompatiable type (please kindly see the ones in red). How should i solve this issue? Or isit that i have coded wrongly? Please advise.

1 import java.util.*;
  2 import java.text.*;
  3 
  4 class Game{
  5 
  6     public static Square [] squares (int size, double value){
  7         Square [] squares = new Square[size];
  8         for (int i = 0; i < squares.length; i++){
  9             [B]squares[i] = value[/B];
 10         }  return squares;
 11     }
 12 
 13     public static void main(String[] args){
 14         // declare the necessary variables
 15         int M, squaretype;
 16         double curPoints = 0.00;
 17         double multiplier, value;
 18       
 19         Scanner sc = new Scanner(System.in);
 20         M = sc.nextInt();
 21         Square[] squares = new Square[M];
 22         SpecialSquare us = new SpecialSquare();
 23 
 24         for (int i = 0; i < M; i++){
 25             squaretype = sc.nextInt();
 26             value = sc.nextDouble();
 27             if (squaretype == 1){
 28                 multiplier = sc.nextDouble(); 
 29                 us._value = value;
 30                 us._multiplier = multiplier;
 31                 squares[i] = us;
 32             }else{
 33                 squares[i] = new Square();
 34                 squares[i]._value = value;
 35             }
 36             curPoints = squares[i].changePoints(curPoints);
 37         }
 38         DecimalFormat twoDecimalFormat = new DecimalFormat("0.00"); // format to 2 decimal place
 39         System.out.println("Final score: " + twoDecimalFormat.format(curPoints));
 40     }
 41 }
 42 
 43 class Square{
 44 
 45     double _value; // value which can be positive or negative
 46 
 47     public double getValue() {
 48         return _value;
 49     }
 50 
 51     public double changePoints(double curPoints){
 52         return (curPoints + _value);
 53     }
 54 }
 55 
 56 class SpecialSquare extends Square{
 57 
 58     double _multiplier;
 59 
 60     public double getMultiplier (){
 61         return _multiplier;
 62     }
 63 
 64     public double changePoints(double curPoints){
 65         return((curPoints*_multiplier)+ _value);
 66     }
 67 }

[JamesCherrill]

Since its an array of Squares you can only put a Square or a UniqueSquare in it.

[janice91]

Since its an array of Squares you can only put a Square or a UniqueSquare in it.

Dear James,

Could you please kindly show me an example using my codes? As i am still unclearly of what you are indicating.

Thank you so much!:)

[JamesCherrill]

when you prompt the user for which kind of Square you can then add that to the array...

if (squareType ==1) {
   squares[i] = new Square();
   // etc
} else {
   squares[i] = new UniqueSquare ();
   // etc
}

Don't wait for someone else to tell you everything - try things out, experiment, see what works. That's the way to learn.

[janice91]

when you prompt the user for which kind of Square you can then add that to the array...

if (squareType ==1) {
   squares[i] = new Square();
   // etc
} else {
   squares[i] = new UniqueSquare ();
   // etc
}

Don't wait for someone else to tell you everything - try things out, experiment, see what works. That's the way to learn.

Thanks James. I have actually resolved the issue after the post which i posted:)

[janice91]

Dear Experts,

Thanks alot for all your kind and active response. I have managed to resolved those issues as mentioned in the previous post. However, i need your guidance in resolving my "dice" issue in my codes.

Using back my sample input and output to explain the dice concept:

Here's the sample input:
5
0 5.25 // Array position [0]
0 -3.14 // Array position [1]
1 2.17 1.50 // Array position [2]
0 5.39 // Array position [3]
1 -3.32 2.00 // Array position [4]
3 3 1 2 // This row is to indicate dices value for each round (in this case there are 4 turns all together)

Explanation:

After 1st turn we are on square 3, hence we add 5.39 to our points
After 2nd turn we are on square 1 ((3+3)%5), hence we add -3.14 to our points
After 3rd turn we are on square 2 (1+1), hence we multiply by 1.5 and add 2.17 to our points
After 4th turn we are on square 4 (2+2), hence we multiple by 2 and add -3.32 (total 7.77)

I am now currently working on the part below and i need experts to kindly help me out.

38             Vector<E> myVector;
 39             myVector = new Vector<E>;
 40 
 41             while (sc.hasNext()){
 42             dicevalue = sc.nextInt();
 43             }

Here is the full version of my codes:

1 import java.util.*;
  2 import java.text.*;
  3 
  4 class Game{
  5 
  6 // public static Square [] squares (int size, double value){
  7       // Square [] squares = new Square[size];
  8     //   for (int i = 0; i < squares.length; i++){
  9   //         squares[i] = value;
 10      //   }  return squares;
 11   // }
 12 
 13     public static void main(String[] args){
 14         // declare the necessary variables
 15         int M, squaretype, dicevalue;
 16         double curPoints = 0.00;
 17         double multiplier, value;
 18 
 19         Scanner sc = new Scanner(System.in);
 20         M = sc.nextInt();
 21         Square[] squares = new Square[M];
 22         SpecialSquare us = new SpecialSquare();
 23 
 24         for (int i = 0; i < M; i++){
 25             squaretype = sc.nextInt();
 26             value = sc.nextDouble();
 27 
 28            if (squaretype == 1){
 29                 multiplier = sc.nextDouble();
 30                 us._value = value;
 31                 us._multiplier = multiplier;
 32                 squares[i] = us;
 33             }else{
 34                 squares[i] = new Square();
 35                 squares[i]._value = value;
 36             }
 37 
 38             Vector<E> myVector;
 39             myVector = new Vector<E>;
 40 
 41             while (sc.hasNext()){
 42             dicevalue = sc.nextInt();
 43             }
 44 
 45             curPoints = squares[i].changePoints(curPoints);
 46         }
 47         DecimalFormat twoDecimalFormat = new DecimalFormat("0.00"); // format to 2 decimal place
 48         System.out.println("Final score: " + twoDecimalFormat.format(curPoints));
 49     }
 50 }
 51 
 52 class Square{
 53 
 54     double _value; // value which can be positive or negative
 55 
 56     public double getValue() {
 57         return _value;
 58     }
 59 
 60     public double changePoints(double curPoints){
 61         return (curPoints + _value);
 62     }
 63 }
 64 
 65 class SpecialSquare extends Square{
 66 
 67     double _multiplier;
 68 
 69     public double getMultiplier (){
 70         return _multiplier;
 71     }
 72 
 73     public double changePoints(double curPoints){
 74         return((curPoints*_multiplier)+ _value);
 75     }
 76 }

Thank you so much

[NormR1]

i need experts to kindly help me out.

Can you explain what your problem is?

[JamesCherrill]

You still have a problem around line 30 - you correctly create a new Square when you need one, but you only create one SpecialSquare, and you keep changing its values. You should create a new SpecialSquare every time you need one as well.

I cannot guess what the Vector is for. Maybe you can tell us?

As for the dice - it looks like you keep throwing a die to see how many squares to move (wrapping round from the end to the beginning again) - so you would typically code that as a loop where you get a new random number, update the "current square" index, update the current points, and repeat until you have done enough moves.