Question

我正在尝试制作一个简单的赔率和赔率游戏。该程序可以完美运行直到“ 1”。问题是：它没有直接将“ finger”和“ computer”相乘，而是直接给出了“ computer”的值，尽管我在其余代码中没有遇到任何错误，但是我也没有任何输出。我将“名称”，“ oe”和“手指”设为静态，以便可以在循环外使用它们。

import java.util.Scanner;
import java.util.Random;

public class OddsAndEvens {
static String name; 
static String oe;
static int finger;

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.println("Let’s play a game called “Odds and Evens”");
    System.out.println("What is your name?");
    String name = input.next();
    while (true) {

        System.out.println("Hello " + name + " which one do you choose? (O)dds or (E)vens?");
        String oe = input.next();

        if (oe.equalsIgnoreCase("e")) {
            System.out.println(name + " has picked evens! The computer will be odds.");
            break;
        }
        if (oe.equalsIgnoreCase("o")) {
            System.out.println(name + " has picked odds! The computer will be evens.");
            break;
        } else {
            System.out.println("You have typed an invalid answer, lets try again");
        }
    }

    while (true) {
        System.out.print("How many \"fingers\" do you put out? ");
        int finger = input.nextInt();
        if (finger >= 0 && finger <= 5) {
            break;
        } else {
            System.out.println("Please write a number between 0 and 5");
        }
    }

    Random rand = new Random();
    int computer = rand.nextInt(5) + 0;
    System.out.println("Computer plays number " + computer);
    System.out.println("----------------------------------------------");

    int sum = finger + computer; //1<------------------------------
    if (sum % 2 == 0) {
        System.out.println(sum + " is even!");
        if (oe.equalsIgnoreCase("e") && (sum % 2 == 0)) {
            System.out.println(name + " wins!");
        } else {
            System.out.println("Computer wins!");
        }

        if (sum % 2 != 0) {
            System.out.println(sum + " is odd!");
            if (oe.equalsIgnoreCase("o") && (sum % 2 != 0)) {
                System.out.println(name + " wins!");
            } else {
                System.out.println("Computer wins!");
            }


        }
    }

}

}

Answer 1

在第二个while循环中，通过说finger来初始化仅在while循环内有效的新局部变量int finger =，而不是说finger =来调用全局静态变量finger

结果是，全局变量finger尚未初始化，并且sum没有要添加到变量computer的内容。

Answer 2

当您在类中使用静态值时，您不应该在while指令中第二次初始化静态值，因为它们是局部指令-因此，一旦您写入局部值和局部值，便要使用类变量。第二件事是划分您的if。如果检查和是否为奇数，那应该是另一部分，如果它是奇数。它也可以通过if ... else来完成。您的代码：

package stackoverflow;

import java.util.Scanner; 导入java.util.Random;

公共类OddsAndEvens {

static String name; 
static String oe;
static int finger;

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.println("Let’s play a game called “Odds and Evens”");
    System.out.println("What is your name?");
    name = input.next();
    while (true) {

        System.out.println("Hello " + name + " which one do you choose? (O)dds or (E)vens?");
        oe = input.next();

        if (oe.equalsIgnoreCase("e")) {
            System.out.println(name + " has picked evens! The computer will be odds.");
            break;
        }
        if (oe.equalsIgnoreCase("o")) {
            System.out.println(name + " has picked odds! The computer will be evens.");
            break;
        } else {
            System.out.println("You have typed an invalid answer, lets try again");
        }
    }

    while (true) {
        System.out.print("How many \"fingers\" do you put out? ");
        finger = input.nextInt();
        if (finger >= 0 && finger <= 5) {
            break;
        } else {
            System.out.println("Please write a number between 0 and 5");
        }
    }

    Random rand = new Random();
    int computer = rand.nextInt(5) + 0;
    System.out.println("Computer plays number " + computer);
    System.out.println("----------------------------------------------");

    int sum = finger + computer; //1<------------------------------
    if (sum % 2 == 0) {
        System.out.println(sum + " is even!");
        if (oe.equalsIgnoreCase("e") && (sum % 2 == 0)) {
            System.out.println(name + " wins!");
        } else {
            System.out.println("Computer wins!");
        }
    }
    if (sum % 2 != 0) {
            System.out.println(sum + " is odd!");
            if (oe.equalsIgnoreCase("o") && (sum % 2 != 0)) {
                System.out.println(name + " wins!");
            } else {
                System.out.println("Computer wins!");
            }


    }

}

Answer 3

您遇到的问题是，您要两次声明变量“名称”，“ oe”和“手指”。您应该只写int finger = input.nextInt();而不是finger = input.nextInt();，因为在您的代码中，您是在循环内声明一个新的变量calls finger，并在循环内使用它，当您的程序移至循环外时，它将使用静态可变手指巫婆将等于零，这就是为什么您总是得到计算机的价值。

由于相同的原因您没有得到任何输出，您要更新的“ oe”与您在if语句中测试的“ oe”不同。

您是if语句也混在一起，第二个if语句在第一个if语句之内。

您的新代码应该是：

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.println("Let’s play a game called “Odds and Evens”");
    System.out.println("What is your name?");
    name = input.next();
    while (true) {

        System.out.println("Hello " + name + " which one do you choose? (O)dds or (E)vens?");
        oe = input.next();

        if (oe.equalsIgnoreCase("e")) {
            System.out.println(name + " has picked evens! The computer will be odds.");
            break;
        }
        if (oe.equalsIgnoreCase("o")) {
            System.out.println(name + " has picked odds! The computer will be evens.");
            break;
        } else {
            System.out.println("You have typed an invalid answer, lets try again");
        }
    }

    while (true) {
        System.out.print("How many \"fingers\" do you put out? ");
        finger = input.nextInt();
        if (finger >= 0 && finger <= 5) {
            break;
        } else {
            System.out.println("Please write a number between 0 and 5");
        }
    }

    Random rand = new Random();
    int computer = rand.nextInt(5) + 0;
    System.out.println("Computer plays number " + computer);
    System.out.println("----------------------------------------------");

    int sum = finger + computer; //1<------------------------------
    if (sum % 2 == 0) {
        System.out.println(sum + " is even!");
        if (oe.equalsIgnoreCase("e") && (sum % 2 == 0)) {
            System.out.println(name + " wins!");
        } else {
            System.out.println("Computer wins!");
        }
    }

    else {
        System.out.println(sum + " is odd!");
        if (oe.equalsIgnoreCase("o") && (sum % 2 != 0)) {
            System.out.println(name + " wins!");
        } else {
                System.out.println("Computer wins!");
        }
    }
}
}

在操作中使用静态变量

3 个答案: