Question

我正在尝试使用do while语句（在此必需）来声明一个人获得的分数，但是我的do语句中的嵌套if语句似乎没有正确递增（即，无论是否会给出0％什么）？我写错了什么不是递增我的正确变量？

以下是我的代码

Scanner input = new Scanner(System.in);
int q1 = 2, //answer 1 correct answer
 q2 = 1, //answer 2 correct answer
 q3 = 3, //answer 3 correct answer
 correct = 0, //amount correct
 answer1, //store answer1
 answer2, //store answer2
 answer3; //store answer 3

System.out.printf("%n Question #1.) What is the capital of Iowa?"); //display question
System.out.printf("%n 1.) Iowa City \t 2.) Des Moines \t 3.) Dubuque"); //display answer
System.out.printf("%n Your answer: ");
answer1 = input.nextInt(); //input becomes initial value

while (answer1 < 1 || answer1 > 3) //while loop to check if answer is valid
{
 System.out.printf("%n Invalid Answer please enter a valid answer: "); //ask for input if not valid
 answer1 = input.nextInt();
}

switch (answer1) //switch statement for input types of answer1
{
 case 1:
  System.out.printf("%n Incorrect"); //if input 1 it is incorrect
  break; //go to next part of code

 case 2:
  System.out.printf("%n Correct"); //if input 2 it is correct
  break;

 case 3:
  System.out.printf("%n Incorrect"); //if input 3 it is incorrect
  break;
}


System.out.printf("%n Question #2.) Where is Iowa?"); //display question
System.out.printf("%n 1.) Midwest \t 2.) South \t 3.) Northeast"); //display answer
System.out.printf("%n Your answer: ");
answer2 = input.nextInt(); //input becomes initial value

while (answer2 < 1 || answer2 > 3) //make sure answer is valid
{
 System.out.printf("%n Invalid Answer please enter a valid answer: "); //ask for valid input
 answer2 = input.nextInt();
}

switch (answer2) //switch statement for chosen answers
{
 case 1:
  System.out.printf("%n Correct"); //correct if input is 1
  break;

 case 2:
  System.out.printf("%n Incorrect"); //incorrect for answer 2
  break;

 case 3:
  System.out.printf("%n Incorrect"); //incorrect for answer 3
  break;
}

System.out.printf("%n Question #3.) Who is the new president of UIowa?"); //display question
System.out.printf("%n 1.) Sally Mason \t 2.) Barack Obama \t 3.) Bruce Harreld"); //display answer
System.out.printf("%n Your answer: ");
answer3 = input.nextInt(); //input becomes initial value

while (answer3 < 1 || answer3 > 3) //make sure valid answer
{
 System.out.printf("%n Invalid Answer please enter a valid answer: "); //ask for valid answer
 answer3 = input.nextInt();
}

switch (answer3) //switch to give output depending on answer
{
 case 1:
  System.out.printf("%n Incorrect"); //if input is 1
  break;

 case 2:
  System.out.printf("%n Incorrect"); //if input is 2 this statement
  break;

 case 3:
  System.out.printf("%n Correct"); //if input is 3 this statement
  break;
}

do {
 if (answer1 == q1) {
  correct++;
 }
 if (answer2 == q2) {
  correct++;
 }
 if (answer3 == q3) {
  correct++;
 }
} while (correct <= 3);
if (correct == 3) {
 System.out.printf("%n 100%%");
} else if (correct == 2) {
 System.out.printf("%n 66.67%%");
} else if (correct == 1) {
 System.out.printf("%n 33.33%%");
} else {
 System.out.printf("%n 0%%");
}
} //end method
} //end class

Answer 1

主要问题是你实际上并不需要do-while循环 - 删除它并显示正确的结果。

在您继续循环直到正确的变量值为4或更大时，会发生什么。（这意味着如果没有正确回答你的问题，你就会有一个无限循环。）当你的逻辑去打印结果时，正确的值为4或更多意味着没有触发if条件，导致最终否则执行并显示0％。

还有许多其他方法可以简化和改进您的代码 - 我假设您只是在学习该语言。

做一部分while while语句不增加我的正确计数？

1 个答案: