Question

我们正在学习选择，并且必须为摇滚，纸张，剪刀游戏编写程序。我的程序运行没有错误，但它只打印“计算机是____。你是____。”我无法弄清楚为什么它不打印你赢/输？这是一个平局声明。

// Solution for exercise 3.17
import java.util.Scanner;

public class PA6c {
    public static void main(String[] args) {

    Scanner input = new Scanner(System.in);

    // Get user input for number associated with rock, paper, or scissor
    System.out.print("Enter a number 0-2: ");

    int userNumber = input.nextInt();

    // Generate random number for computer
    int compNumber = (int)(Math.random() * 10);

    // Declare rock, paper, and scissor
    int scissor = 0;
    int rock = 1;
    int paper = 2;

    // Determine what the computer is
    if (compNumber == scissor) {
        System.out.print("The computer is scissor. ");
    }
    else if (compNumber == rock) {
        System.out.print("The computer is rock. ");
    }
    else {
        System.out.print("The computer is paper. ");
    }

    // Determine what the user is
    if (userNumber == scissor) {
        System.out.print("You are scissor. ");
    }
    else if (userNumber == rock) {
        System.out.print("You are rock. ");
    }
    else {
        System.out.print("You are paper. ");
    }

    // Determine who won
    if (compNumber == scissor) {
        if (userNumber == scissor) {
            System.out.println("It is a draw.");
        }
        else if (userNumber == rock) {
            System.out.println("You win.");
        }
        else if (userNumber == paper) {
            System.out.println("You lose.");
        }
    }
    else if (compNumber == rock) {
        if (userNumber == scissor) {
            System.out.println("You lose.");
        }
        else if (userNumber == rock) {
            System.out.println("It is a draw.");
        }
        else if (userNumber == paper) {
            System.out.println("You win.");
        }
    }
    else if (compNumber == paper) {
        if (userNumber == scissor) {
            System.out.println("You win.");
        }
        else if (userNumber == rock) {
            System.out.println("You lose.");
        }
        else if (userNumber == paper) {
            System.out.println("It is a draw.");
        }
        }
    }
}

Answer 1

问题在于您尝试获取随机数的方式。在任何时候你都需要{0,1,2}的随机数，但Math.Random()*10会给你{0,1,2,3,4,5,6,7,8,9}范围内的数字，所以你的目的在这里被打败了。因此，请确保compNumber始终是{0,1,2}之一。

用此替换你的随机数生成线，

Random rand = new Random();
compNumber = rand.nextInt(0 , 3); // will give you 0 or 1 or 2

为什么不打印所有三个语句？

1 个答案: