Java 使用关系运算符查找分数

因此，对于我代码的最后一部分，我试图根据用户正确回答的问题数量做出评论。如果用户得到了3个或更多的正确答案，我想留下一个祝贺。但是如果用户得到的少于这个，我想留下一条评论，以便进一步研究。我知道我应该使用关系运算符来解决这个问题，但我有点困惑于我到底是如何做到的

import java.util.Scanner; 

public class quizcreation
{
   public static void main (String [] args)
   {
   Scanner input = new Scanner (System.in);

   System.out.println ("If your answer is not one of the options, it will be considered incorrect.");
   System.out.println();

   //Question 1
   System.out.println ("T/F: Harry Potter was an only child.");
   String answer1 = input.next();

   if (answer1.equals("True"))
   {
      System.out.println("That is correct! Harry was an only child.");
      }   

   else if (answer1.equals("true"))
   {
      System.out.println("That is correct! Harry was an only child.");
      }
   else if (answer1.equals("TRUE"))
   {
      System.out.println("That is correct! Harry was an only child.");
      }
   else if (answer1.equals("t"))
   {
      System.out.println("That is correct! Harry was an only child.");
      }

   else if (answer1.equals("T"))
   {
      System.out.println("That is correct! Harry was an only child.");
      }

   else 
   {

      System.out.println("Sorry that is incorrect. Harry was an only child.");
    } 

   System.out.println();

   //Question 2
   System.out.println ("T/F: Ron Weasley has more than one brother.");
   String answer2 = input.next();

   if (answer2.equals("True"))
   {
      System.out.println(" 100% correct! Ron has 2 twin brothers.");
      }
   else if (answer2.equals("true"))
   {
      System.out.println("100% correct! Ron has 2 twin brothers.");
      }

   else if (answer2.equals("TRUE"))
   {
      System.out.println("100% correct! Ron has 2 twin brothers.");
      }
   else if (answer2.equals("t"))
   {
      System.out.println("100% correct! Ron has 2 twin brothers.");
      }
   else if (answer2.equals("T"))
   {
      System.out.println ("100% correct! Ron has 2 twin brothers.");
      }
   else 
   {
      System.out.println ("Sorry that is incorrect. Ron has 2 twin brothers.");
      }
   System.out.println();   

   //Question 3
   System.out.println("What was the first name of Harry's uncle?");
   System.out.println("a) Remus");
   System.out.println("b) Snape");
   System.out.println("c) Sirius");

   String answer3 = input.next();

   if (answer3.equals("a"))
   {
      System.out.println ("Sorry that is incorrect. ");
      }

   else if (answer3.equals ("A"))
   {
      System.out.println ("Sorry that is incorrect.");
      }

   else if (answer3.equals ("b"))
   {
      System.out.println ("Sorry that is incorrect. ");
      }

   else if (answer3.equals("B"))
   {
      System.out.println ("Sorry that is incorrect. ");
      }

   else if (answer3.equals ("C"))
   {
      System.out.println ("That is correct! ");
      }

   else if (answer3.equals ("c"))
   {
      System.out.println ("That is correct! ");
      }

   else 
   {
      System.out.println ("THAT WASN'T EVEN AN OPTION YO. This is incorrect.");
      }
   System.out.println();   

   //question 4

   System.out.println("What is the name of one of the houses at Hogwarts");
   String answer4 = input.next();

   if (answer4.equals("Gryffindor"))
   {
      System.out.println ("You are correct! Students from Gryffindor are known for their bravery.");
      }

   else if (answer4.equals("gryffindor"))
   {
      System.out.println("You are correct! Students from Gryffindor are known for their bravery.");
      }
   else if (answer4.equals("Slytherin"))
   {
      System.out.println( "You are correct! Slytherin are known for being cunning and ambitious.");
      }
   else if (answer4.equals("slytherin"))
   {
      System.out.println(" You are correct! Slytherins are known for being cunning and ambitious.");
      }
   else if (answer4.equals("Ravenclaw"))
   {
      System.out.println("You are correct! Ravenclaws are known for their intelligence.");
      }
   else if (answer4.equals("ravenclaw"))
   {
      System.out.println("You are correct! Ravenclaws are known for their intelligence.");
      }
   else if (answer4.equals ("Hufflepuff"))
   {
      System.out.println("You are correct! Hufflepuffs are known for their kindness.");
      }
   else if (answer4.equals ("hufflepuff"))
   {
      System.out.println("You are correct! Hufflepuffs are known for their kindess.");
      }
   else 
   {
      System.out.println(" Sorry that is incorrect :(");
      }
   }
}

---

您可以在代码顶部声明一个变量，如下所示：

int correct = 0;

然后，一旦它进入一个正确答案，通过添加一个来更新变量，即

correct++

然后在代码的底部，输入一个新的
if
语句

if (correct >= 3) {
            //message here
        } else {
            //other message
        }

您还可以使用
equalsIgnoreCase
和
|
（或）大幅缩短代码

例如：

if (answer1.equalsIgnoreCase("True") || answer1.equalsIgnoreCase("T")) {
            System.out.println("That is correct! Harry was an only child.");
            correct++;
        } else {
            System.out.println("Sorry that is incorrect. Harry was an only child.");
        }

首先，我建议您使用
equalsIgnoreCase
方法来比较
字符串
，以避免出现丑陋的倍数
equals
。你可以阅读更多关于它的内容

此外，要确定正确答案的数量，请使用简单的
int
变量。对于每个正确的响应，递增它。最后，根据计数器的最终值做出决定

这是代码的简化版本：

Scanner input = new Scanner(System.in);
int correctAnswersCounter = 0;

System.out.println("If your answer is not one of the options, it will be considered incorrect.");
System.out.println();

//Question 1
System.out.println("T/F: Harry Potter was an only child.");
String answer1 = input.next();

// equalsIgnoreCase() works for all variations like 'true', 'TRUE', 'TrUe', 'truE' etc. for example

if (answer1.equalsIgnoreCase("true") || answer1.equalsIgnoreCase("t")) {
    System.out.println("That is correct! Harry was an only child.");
    correctAnswersCounter++;
} else {
    System.out.println("Sorry that is incorrect. Harry was an only child.");
}

System.out.println();

//Question 2
System.out.println("T/F: Ron Weasley has more than one brother.");
String answer2 = input.next();

if (answer2.equalsIgnoreCase("true") || answer2.equalsIgnoreCase("t")) {
    System.out.println(" 100% correct! Ron has 2 twin brothers.");
    correctAnswersCounter++;
} else {
    System.out.println("Sorry that is incorrect. Ron has 2 twin brothers.");
}
System.out.println();

//Question 3
System.out.println("What was the first name of Harry's uncle?");
System.out.println("a) Remus");
System.out.println("b) Snape");
System.out.println("c) Sirius");

String answer3 = input.next();

if (answer3.equalsIgnoreCase("a")) {
    System.out.println("Sorry that is incorrect. ");
} else if (answer3.equalsIgnoreCase("b")) {
    System.out.println("Sorry that is incorrect. ");
} else if (answer3.equalsIgnoreCase("c")) {
    System.out.println("That is correct! ");
    correctAnswersCounter++;
} else {
    System.out.println("THAT WASN'T EVEN AN OPTION YO. This is incorrect.");
}
System.out.println();

//question 4

System.out.println("What is the name of one of the houses at Hogwarts");
String answer4 = input.next();

if (answer4.equalsIgnoreCase("Gryffindor")) {
    System.out.println("You are correct! Students from Gryffindor are known for their bravery.");
    correctAnswersCounter++;
} else if (answer4.equalsIgnoreCase("Slytherin")) {
    System.out.println("You are correct! Slytherin are known for being cunning and ambitious.");
    correctAnswersCounter++;
} else if (answer4.equals("Ravenclaw")) {
    System.out.println("You are correct! Ravenclaws are known for their intelligence.");
    correctAnswersCounter++;
} else if (answer4.equals("Hufflepuff")) {
    System.out.println("You are correct! Hufflepuffs are known for their kindness.");
    correctAnswersCounter++;
} else {
    System.out.println(" Sorry that is incorrect :(");
}

// now make a decision based on the value of correctAnswersCounter
if(correctAnswersCounter > 3) {
    System.out.println("Congrats!");
}
else {
    System.out.println("Try harder next time!");
}

使用
equalsIgnoreCase
而不是equals，并使用
|
条件使代码更好。注意，您可能还应该使用
input.nextLine（）
而不是
input.next（）
，以避免意外地同时回答两个问题（尝试输入
t
）在第一个问题上看我的意思）。另一种检查答案的方法是
Arrays.asList（“TRUE”，“T”）.contains（input.toUppercase（））
——好的地方是，创建一个“question”类更容易，从而进一步缩减代码。