数字猜测程序错误？

Question

我想创建一个数字猜测程序，用户输入一个数字，程序会告诉您输入是否太高，太低或正确。程序选择0-100之间的随机数。问题是，当我开始测试程序时，当我选择1时，程序告诉我猜测过高。但是这是错误的，因为程序只能做整数。如果用户输入的号码不等于随机数，则1必须太低。 有人可以看看我的代码，看看是否有什么奇怪的。

int guess; 
    int guess2; 
    int guess3; 
    int guess4; 
    int guess5; 
    int random = (int)Math.random() * 100; 
    Scanner input = new Scanner(System.in); 

    System.out.println("Try to guess a number between 0-100. You have five chances."); 
    guess = input.nextInt(); 
    if(guess >= 100 || guess <= 0){ 
     System.out.println("Error, that is not a number between 0-100."); 
    } else if(guess > random){ 
     System.out.println("The guess is too high."); 
    } else if(guess < random){ 
     System.out.println("The guess is too low."); 
    } else if(guess == random){ 
     System.out.println("YOU WIN"); 
    } else{ 
    } 

    System.out.println("Second guess."); 
    guess2 = input.nextInt(); 
    if(guess2 >= 100 || guess2 <= 0){ 
     System.out.println("Error, that is not a number between 0-100."); 
    } else if(guess2 > random){ 
     System.out.println("The guess is too high."); 
    } else if(guess2 < random){ 
     System.out.println("The guess is too low."); 
    } else if(guess2 == random){ 
     System.out.println("YOU WIN"); 
    } else{ 
    } 

    System.out.println("Third guess."); 
    guess3 = input.nextInt(); 
    if(guess3 >= 100 || guess3 <= 0){ 
     System.out.println("Error, that is not a number between 0-100."); 
    } else if(guess3 > random){ 
     System.out.println("The guess is too high."); 
    } else if(guess3 < random){ 
     System.out.println("The guess is too low."); 
    } else if(guess3 == random){ 
     System.out.println("YOU WIN"); 
    } else{ 
    } 

    System.out.println("Fourth guess."); 
    guess4 = input.nextInt(); 
    if(guess4 >= 100 || guess4 <= 0){ 
     System.out.println("Error, that is not a number between 0-100."); 
    } else if(guess4 > random){ 
     System.out.println("The guess is too high."); 
    } else if(guess4 < random){ 
     System.out.println("The guess is too low."); 
    } else if(guess4 == random){ 
     System.out.println("YOU WIN"); 
    } else{ 
    } 

    System.out.println("Last guess."); 
    guess5 = input.nextInt(); 
    if(guess5 >= 100 || guess5 <= 0){ 
     System.out.println("Error, that is not a number between 0-100."); 
    } else if(guess5 > random){ 
     System.out.println("The guess is too high."); 
    } else if(guess5 < random){ 
     System.out.println("The guess is too low."); 
    } else if(guess5 == random){ 
     System.out.println("YOU WIN"); 
    } else{ 
    } 

Answer 1

它看起来不错，但你需要改变这一行投：

int random = (int)Math.random() * 100; 

到：

int random = (int)(Math.random() * 100); 

目前您的随机数总是0.为什么？因为您正在将Math.random（）转换为int类型，而在Java中则意味着小数点后的所有内容都会丢失。 （因此，0.85将变成0. 0 * 100 = 0）。通过在Math.random（）乘以100之后添加我们施加的括号。

另外，请注意，您的随机数可能为0，但永远不会100. Math.random（）返回一个大于或等于0且小于1的数字。当您将其转换为int时，99.9999将变为99.

如果您希望它真的是0-100 ，你会想要：

int random = (int)(Math.random() * 101); 

另外，你可能希望游戏在玩家获胜后终止。因此，改变这种：

System.out.println("YOU WIN"); 

这样：

System.out.println("YOU WIN"); 
return; //end 

最后，你的空else子句永远不会被调用。你有条件超出范围，大于随机，小于随机，等于随机。您可以安全地删除该死的代码。

Answer 2

变化int random = (int)Math.random() * 100;到int random = (int)(Math.random() * 100);

Answer 3

有2个主要问题与您的代码：

首先：

您未能投随机变量马上所以随机值的值始终为0。

合适的款式是：

int random = (int)(Math.random() * 100); 

二：

你如果结构可怕：

例如：

if(guess >= 100 || guess <= 0){ 

1. 你说猜测是且等于100
2. 你说猜测是少且等于0
3. 您使用||操作数，而不是&&检查数量在0范围100

试试这个：

if (guess <= 100 && guess >= 0) { 
     if (guess > random) { 
      System.out.println("The guess is too high."); 
     } else if (guess < random) { 
      System.out.println("The guess is too low."); 
     } else if (guess == random) { 
      System.out.println("YOU WIN"); 
     } 
    } else { 
     System.out.println("Error, that is not a number between 0-100."); 
    } 

说明：如果居兴数量为100和0之间，做以下。如果它不告诉用户他或她不在该范围内。

Answer 4

你可以这样做你的代码。轻松你可以使用for循环

int guess; 
    int random = (int) (Math.random() * 100); 
    Scanner input = new Scanner(System.in); 

    System.out.println("Try to guess a number between 0-100. You have five chances."); 
    for (int i = 0; i < 5; i++) { 
     System.out.println("Chance " + (i + 1)); 
     guess = input.nextInt(); 
     if (guess >= 100 || guess <= 0) { 
      System.out.println("Error, that is not a number between 0-100."); 
     } else if (guess > random) { 
      System.out.println("The guess is too high."); 
     } else if (guess < random) { 
      System.out.println("The guess is too low."); 
     } else if (guess == random) { 
      System.out.println("YOU WIN"); 
      break; 
     } 
    } 
    System.out.println(random);