Question

Java language: C

Write a game program that allows the user to collect 4 tokens hidden in an array (cells) of size 10. The program asks the user to select a cell. Determine if there is a token in that cell or not, and give the user appropriate feedback. This program should keep letting user to select until the all tokens are collected. The program should display the total number of selections. Use rand_position

Example input/output:

There are four tokens. Select from the following cells for the tokens: 0 1 2 3 4 5 6 7 8 9

Enter your selection: 2 Output: Sorry, there is no token in cell #2

Enter your selection: 5

Output: Congrats! You have collected a token from cell #5

Enter your selection: 7

Output: Sorry, there is no token in cell #2

Enter your selection: 3

Output: Congrats! You have collected a token from cell #3

Enter your selection: 9

Output: Congrats! You have collected a token from cell #9

Enter your selection: 1

Output: Sorry, there is no token in cell #1

Enter your selection: 0

Output: Congrats! You have collected a token from cell #0 All tokens are collected! You have made 6 selections.

Answer 1

JAVA PROGRAM

package test;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
* TheGame class
*/
public class TheGame {
  
   public static void main(String[] args){
      
       TheGame tg = new TheGame(); //create an instance of TheGame class
      
       //this will create gameArray of size 10 with 4 hidden tokens in random indexes
       //hidden tokens will be identified with value 1
       int[] gameArray = tg.rand_position(10,4);
      
       //If the array needs to be printed the following line can be uncommemted
       //System.out.println(Arrays.toString(gameArray));
      
       int tokenCounter = 0 ; //to check number of hidden tokens collected
       int numberOfSelections = 0; // to check total selections made
       Scanner sc = new Scanner(System.in); // Scanner instance is created to read user selection
      
       System.out.println("There are four tokens. Select from the following cells for the tokens: 0 1 2 3 4 5 6 7 8 9");
      
       while(tokenCounter < 4){ //iterate as long as all tokens are not collected
           System.out.println("Enter your selection:");
           int indexSelected = sc.nextInt();
           if(indexSelected>=0 && indexSelected < 10){ //if this is a valid selection
               if(gameArray[indexSelected]==1){ //if this is a hidden token
                   tokenCounter++; // increase the counter by 1 as a token is collected
                   System.out.println("Congrats! You have collected a token from cell #"+indexSelected);
               }else{ //if this cell does not contain a token
                   System.out.println("Sorry, there is no token in cell #"+indexSelected);
               }
           }else{ //if the selection is improper
               System.out.println("This is not a valid selection!");
           }
          
           numberOfSelections++;//increase the number of selection attempt
       }
      
       //end of while loop - means all tokens are collected
       sc.close();//close scanner
       System.out.println("All tokens are collected! You have made "+numberOfSelections+" selections.");
      
   }
  
   /**
   * This method will create int array of arrSize , having numOfTokens number of hidden token in it
   * at random indexes
   * @param arrSize
   * @param numOfTokens
   * @return
   */
   private int[] rand_position(int arrSize, int numOfTokens){
       int[] arr = new int[arrSize]; //initialize array with arrSize
      
       List<Integer> s= new ArrayList<Integer>(); //this will hold random index location
       int currentRandom ;
      
       //create numOfTokens times of random index for hidden tokens
       for(int p = 1; p <= numOfTokens ; p++){
           //This do-while loop will generate random index
           //as long as the random index generated is there in list s
           do{
               currentRandom = (int)(Math.random()*arrSize);
           }while(s.contains(currentRandom));
          
           s.add(currentRandom);   //means currentIndex is a unique to the list s, hence add it
       }
      
       //populate the array
       for(int i = 0 ; i < arrSize; i++){
           if(s.contains(i)){
               arr[i] = 1;//mark all hidden token index location with value 1
           }else{
               arr[i] = 0;//all other are 0
           }
       }
      
       return arr;
   }

}

OUTPUT:

There are four tokens. Select from the following cells for the tokens: 0 1 2 3 4 5 6 7 8 9
Enter your selection:
0
Sorry, there is no token in cell #0
Enter your selection:
1
Congrats! You have collected a token from cell #1
Enter your selection:
2
Sorry, there is no token in cell #2
Enter your selection:
3
Sorry, there is no token in cell #3
Enter your selection:
4
Sorry, there is no token in cell #4
Enter your selection:
15
This is not a valid selection!
Enter your selection:
5
Congrats! You have collected a token from cell #5
Enter your selection:
6
Congrats! You have collected a token from cell #6
Enter your selection:
7
Congrats! You have collected a token from cell #7
All tokens are collected! You have made 9 selections.

EXPLANATION

All the required code comments and explanation are given within code.