所以我的问题是在我的代码中我需要它询问5个问题，然后询问用户他/她是否想要继续或停止。如果他们选择继续它，应该将它们带回菜单（switch语句），他们可以选择另外一组数学问题。对于switch语句中的每个选项，它应该只有5个数学问题。如果他们选择停止，代码应该计算它正确的问题，并计算正确的percantage。任何提示或我的代码有什么问题..我知道我错过了我的for循环，因为我不确定在哪里放它以及如何使代码与它一起使用。
{
//keyboard reader
Scanner in = new Scanner((System.in));
//3 number variables
int num1;
int num2;
int answer;
int operator;
int question = 0;
int num3;
double questionCount = 0;
double correct = 0;
int i = 0;
while (i < 7)
{
num1 = (int)(1+Math.random()*10);
num2 = (int)(1+Math.random()*10);
num3 = (int)(1+Math.random()*100);
System.out.println("Welcome to the Wsu School of Math! ");
System.out.println("please choose one of the following options for your math Quiz: ");
System.out.println("1: Addition with number 1-10");
System.out.println("2: Additon with numbers 1-100");
System.out.println("3: Subtraction with numbers 1-10");
System.out.println("4: Subtraction with numbers 1-100");
System.out.println("5: Multipication with numbers 1-10");
System.out.println("6: Exit the Quiz");
operator = in.nextInt();
switch (operator)
{
case 1: System.out.println(num1+"+"+num2+"=");
question = num1 + num2;
break;
case 2: System.out.println(num1+"+"+num3+"=");
question = num1 + num3;
break;
case 3: System.out.println(num1+"-"+num2+"=");
if(num1 < num2)
{
int temp = num1;
num1 = num2;
num2 = temp;
}
question = num1 - num2;
break;
case 4: System.out.println(num3+"-"+num1+"=");
if(num1 > num3)
{
int temp = num1;
num1 = num3;
num3 = temp;
}
question = num1 - num3;
break;
case 5: System.out.println(num1+"*"+num2+"=");
question = num1 * num2;
break;
case 6:
if(operator == 6)
{
System.exit(-1);
}
break;
}
answer = Integer.parseInt(in.next());
if(answer == -99)
{
System.out.print("good bye!\n");
}
else if (answer == question)
{
System.out.print("Correct!\n");
questionCount++;
correct++;
}
else
{
System.out.print("incorrect.\n");
System.out.println("the correct answer is = "+question );
questionCount++;
}
}
System.out.println("Amount of problems attempted: "+questionCount);
System.out.println("Amount of problems Correct: "+ correct);
System.out.println("Percent you got on the test = "+correct/questionCount*100);
}
答案 0 :(得分：4)
尝试写下你的“案例6”：
case 6:
System.out.println("Amount of problems attempted: "+questionCount);
System.out.println("Amount of problems Correct: "+ correct);
System.out.println("Percent you got on the test = "+correct/questionCount*100);
System.exit(-1);
break;
我从他们所在的地方剪下了“System.out.print ...”并将它们放在你的“案例6：”中。但是System.exit（-1）;将关闭该应用程序。如果你想简单地退出while循环，你需要一个布尔值来循环，你会在“case 6”中改变它的值，如下所示：
boolean a = true;
while(a){
//...
case 6:
//...
a = false;
break;
//...
}
或者你可以确保你的（i <7）变得虚假。这取决于你想要达到的目标。希望这有帮助!!!
答案 1 :(得分：0)
尝试如下：
case 6:
// DEL Start
//if(operator == 6)
//{
// System.exit(-1);
//}
// DEL End
break;
}
boolean isEnd = false;
if (operator != 6) { // Add
answer = Integer.parseInt(in.next());
// Add Start
if (answer == question)
{
System.out.print("Correct!\n");
questionCount++;
correct++;
}
else
{
System.out.print("incorrect.\n");
System.out.println("the correct answer is = "+question );
questionCount++;
}
// Add End
// Add Start
}
//
else {
//answer = -99;
isEnd = true;
}
// Add End
//if(answer == -99)
if (isEnd)
{
System.out.print("good bye!\n");
break; // Add
}
// DEL Start
//else if (answer == question)
//{
// System.out.print("Correct!\n");
// questionCount++;
// correct++;
//}
//else
//{
// System.out.print("incorrect.\n");
// System.out.println("the correct answer is = "+question );
// questionCount++;
//}
// DEL End
}
System.out.println("Amount of problems attempted: "+questionCount);
System.out.println("Amount of problems Correct: "+ correct);
System.out.println("Percent you got on the test = "+correct/questionCount*100);
答案 2 :(得分：0)
据我所知，你错过了一个循环。代码的一般结构应如下所示：
Scanner sc = new Scanner(System.in);
for (int questionBlock = 0; questionBlock < 5; questionBlock++) {
System.out.println("select question..");
int blockIndex = sc.nextInt();
for (int question = 0; question < 5; question++) {
//initialize random variables
switch (blockIndex){
case 1:
//do stuff
break;
case 2:
//do other stuff
break;
default:
//wrong input.
}
}
// evaluate results of last 5 questions..
}
当您阅读输入时，您可能希望这样做：
Scanner sc = new Scanner(System.in);
int blockIndex = 0;
while(blockIndex < 1 || blockIndex > 5) {
System.out.println("Please select a question block, by entering it's number..");
String text = sc.next();
try{
if (text.equals("exit")) {
//exit
} else {
blockIndex = Integer.parseInt(text);
continue;
}
}catch (NumberFormatException e) {
//do nothing here
}
System.out.println(text+" was not a valid block number. Please enter an index between 1 and 5!");
}
//rest of code
这将确保您的输入介于1和5之间。此外，通过输入exit