用户输入与数组值的比较

Question

I'm trying to make a lottery game in java to run in the console afterwards with user input. I have a [3][9] array of random numbers between 1-9 in column 1, 10-19 in column 2, until 90, with half the numbers being 0, meaning they aren't part of the game or simply blanks. So far, I have the numbers created in the array and they output fine, but I need to allow the user to have input and the numbers being guessed to start as blanks (or x instead of the number) and when the user actually gets the right number, it would switch that with the number generated previously. This would repeat itself until all the numbers were right, and then a message indicating a win would show.

How can I compare the inputs with the values generated? And how do I hide these values until they are guessed by the user?

Final Edit: If a line is completed with correct numbers, how do I keep track of this to also display message if this happens?

This is the random array index:

import java.util.Arrays;
import java.util.Random;

class Loto {

public static void main(String[] args) {
    int[][] cartao = new int[3][9];
    
    Random rand = new Random();
    for(int i = 0; i< cartao.length; i++){
        for(int j = 0; j< 5; j++){
            int x = rand.nextInt(89) + 1;
            while(cartao[i][x / 10] !=0) {
                x = rand.nextInt(89) + 1;
            }  
            cartao[i][x / 10] = x;
        }
    }
    
    for(int[] row : cartao){
        System.out.println(Arrays.toString(row));
    }        
}
}

Answer 1

You have to store what has been guessed correctly or not. For example you can use an auxiliary boolean matrix though it is not necessary (u can use only your card array, storing correctly guessed guesses has -1 for example), but it is easier to the eye I would say

public class Lotto {
boolean correctlyGuessed[][];
int lottoCard[][];
public Lotto() {
    correctlyGuessed = new boolean[3][9];
    lottoCard = new int[3][9];
    
    Random rand = new Random();
    for(int i = 0; i< lottoCard.length; i++){
        for(int j = 0; j< 5; j++){
            int x = rand.nextInt(89) + 1;
            while(lottoCard[i][x / 10] !=0) {
                x = rand.nextInt(89) + 1;
            }  
            lottoCard[i][x / 10] = x;
        }
    }
}

public boolean guess(int row, int col, int number) {
    if(lottoCard[row][col] == number) {
        correctlyGuessed[row][col] = true;
        return true;
    }
    return false;
}

public boolean hasLottoEnded() {
    for(boolean[] arr:correctlyGuessed) {
        for(boolean guess: arr) {
            if(!guess) //if a guess is still false the game hasn't ended
                return false;
        }
    }
    return true;
}

public int getNumber(int row, int col) {
    return lottoCard[row][col];
}

@Override
public String toString() {
    StringBuilder sb = new StringBuilder();
    for(int row = 0; row < lottoCard.length; row++) {
        for(int col = 0; col < lottoCard[row].length; col++) {
            if(correctlyGuessed[row][col])
                sb.append(lottoCard[row][col] + " ");
            else
                sb.append("X ");

        }
        //spacing
        sb.append("\n");
    }
    return sb.toString();
}

public static void main(String[] args) {
    Lotto card = new Lotto(); 
    
    Scanner sc = new Scanner(System.in);
    while(!card.hasLottoEnded()) { //loop whilst the game hasn't ended
        System.out.println("Row:");
        int row = sc.nextInt();
        System.out.println("Column:");
        int col = sc.nextInt();
        System.out.println("Number:");
        int number = sc.nextInt();
        if(card.guess(row, col, number))
            System.out.println("You have guessed correctly!");
        else
            System.out.println("Wrong guess :(");
        System.out.println(card);
    }
    System.out.println("You win!");
    sc.close();
  }

}