编辑：我有一些更正作为答案。我需要在老虎机中为不同的场景使用另一个do-while循环。我已经找到了这个特定问题的答案，并且已经为想要使用它的人提供答案。
我有一个while while循环无法完成。为了进入do while循环，我需要输入一个数字。除非用户输入内容，否则它不会启动 - 如果输入一个可以理解的字母会出现不匹配错误，但是如果没有用户输入任何内容，我怎么能进入循环？
另外，是否会在另一个do循环中解决它没有完全运行的问题？我对它的逻辑感到困惑，我的伪代码是错误的。谢谢。
import java.util.Scanner;
import java.util.Random;
import java.io.*;
public class Slot2
{
public static void main(String[] args) throws IOException
{
int number;
System.out.println ("Welcome to the Slot Machine Simulator!");
System.out.println ("\nActions\n1. Start a new game\n2. Scores\n3. Exit");
System.out.print ("\nPlease select an action: ");
Scanner keyboard = new Scanner(System.in);
int option = keyboard.nextInt();
while (option != 1 && option != 2 && option != 3)
{
System.out.print ("\nThat is not an option. Please select an item number between 1-3: ");
option = keyboard.nextInt();
break;
}
if (option == 1)
{
String username;
double startingTotal = 100.0;
double userTotal = startingTotal;
System.out.print ("\nBefore the game begins, please enter your name: ");
username = keyboard.next( );
System.out.print ("\nGame start! You will begin with $100.00. Enter a negative value to quit the game. Good luck, " + username + "!");
do **//you have to enter a number here to get the 1st print statement,this is the error**
{
double bet = keyboard.nextDouble();
bet = 0.0;
userTotal = startingTotal - bet;
System.out.print ("You currently have: $%.2f" + startingTotal + "\nHow much would you like to bet?"); **//this is the part of the loop that works**
double winnings = 0.0;
double userFinalTotal = 0.0;
Random generator = new Random();
int slot1 = generator.nextInt(6);
int slot2 = generator.nextInt(6);
int slot3 = generator.nextInt(6);
String firstSlot = "";
switch (slot1)
{
case 0:
firstSlot = "Cherries";
break;
case 1:
firstSlot = "Oranges";
break;
case 2:
firstSlot = "Plums";
break;
case 3:
firstSlot = "Bells";
break;
case 4:
firstSlot = "Melons";
break;
case 5:
firstSlot = "Bars";
break;
}
String secondSlot = "";
switch (slot2)
{
case 0:
secondSlot = "Cherries";
break;
case 1:
secondSlot = "Oranges";
break;
case 2:
secondSlot = "Plums";
break;
case 3:
secondSlot = "Bells";
break;
case 4:
secondSlot = "Melons";
break;
case 5:
secondSlot = "Bars";
break;
}
String thirdSlot = "";
switch (slot3)
{
case 0:
thirdSlot = "Cherries";
break;
case 1:
thirdSlot = "Oranges";
break;
case 2:
thirdSlot = "Plums";
break;
case 3:
thirdSlot = "Bells";
break;
case 4:
thirdSlot = "Melons";
break;
case 5:
thirdSlot = "Bars";
break;
}
System.out.println ("-------------------------------");
System.out.println ("" + firstSlot + " " + secondSlot + " " + thirdSlot);
System.out.print ("-------------------------------");
if (slot1 == slot2 && slot1 == slot3)
{
winnings = bet * 3;
userFinalTotal = userTotal + winnings;
System.out.printf ("\nNumber of matches: 3. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2f", userFinalTotal);
}
else if ((slot1 == slot2 && slot2 != slot3) || (slot1 == slot3 && slot1 != slot2) || (slot2 == slot3 && slot3 != slot1))
{
winnings = bet * 2;
userFinalTotal = userTotal + winnings;
System.out.printf ("\nNumber of matches: 2. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2fn", userFinalTotal);
}
else
{
System.out.printf ("\nNumber of matches: 0. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2f", userFinalTotal);
}
if ((bet < 0) || (userFinalTotal <= 0))
{
break;
}
while (bet > userFinalTotal)
{
System.out.print("\nYour bet is greater than your current total. Please enter a valid amount: ");
bet = keyboard.nextDouble();
}
} while (userTotal > 0);
}
}
}
答案 0 :(得分：0)
尝试将username = keyboard.next( );更改为username = keyboard.nextLine( );，我相信它会有用。
您的do-while循环没有任何问题。
最重要的是，你不应该在while循环中声明这些变量。
String username;
double startingTotal = 100.0;
double userTotal = startingTotal;
答案 1 :(得分：0)
我在do-while循环中有一个printwriter语句，用于打印播放老虎机的每个用户的分数。但是，我认为，因为这个分数打印多次，当它说要查看分数时（选项2）。这是因为使用了变量，还是它在do-while循环中的事实？ import java.util.Scanner; import java.util.Random; import java.io。*;
public class Slot3
{
public static void main(String[] args) throws IOException
{
System.out.println ("Welcome to the Slot Machine Simulator!");
int option = 0;
//if the user selects a 1 or 2 (does not want to exit) then this loop will run
do
{
System.out.println ("\nActions\n1. Start a new game\n2. Scores\n3. Exit");
System.out.print ("\nPlease select an action: ");
Scanner keyboard = new Scanner(System.in);
option = keyboard.nextInt();
keyboard.nextLine();
while (option != 1 && option != 2 && option != 3)
{
System.out.print ("\nThat is not an option. Please select an item number between 1-3: ");
option = keyboard.nextInt();
keyboard.nextLine();
}
//this will occur if the user selects 1 to play the game
if (option == 1)
{
double money = 100.00;
double bet = 0.00;
double winnings = 0.00;
double score = 0.00;
int count = 0;
System.out.print ("\nBefore the game begins, please enter your name: ");
String username = keyboard.nextLine();
System.out.print ("\nGame start! You will begin with $100.00. Enter a negative value to quit the game. Good luck, " + username + "!");
System.out.printf("\nYou currently have $%.2f.", 100.00);
do
{
System.out.printf("\n\nHow much would you like to bet? ");
bet = keyboard.nextDouble();
if ((bet < 0) || (money <= 0))
{
break;
}
while (bet > money)
{
System.out.print("\nYour bet is greater than your current total. Please enter a valid amount: ");
bet = keyboard.nextDouble();
}
//create random numbers
Random generator = new Random();
int slot1 = generator.nextInt(6);
int slot2 = generator.nextInt(6);
int slot3 = generator.nextInt(6);
String firstSlot = "";
switch (slot1)
{
case 0:
firstSlot = "Cherries";
break;
case 1:
firstSlot = "Oranges";
break;
case 2:
firstSlot = "Plums";
break;
case 3:
firstSlot = "Bells";
break;
case 4:
firstSlot = "Melons";
break;
case 5:
firstSlot = "Bars";
break;
}
String secondSlot = "";
switch (slot2)
{
case 0:
secondSlot = "Cherries";
break;
case 1:
secondSlot = "Oranges";
break;
case 2:
secondSlot = "Plums";
break;
case 3:
secondSlot = "Bells";
break;
case 4:
secondSlot = "Melons";
break;
case 5:
secondSlot = "Bars";
break;
}
String thirdSlot = "";
switch (slot3)
{
case 0:
thirdSlot = "Cherries";
break;
case 1:
thirdSlot = "Oranges";
break;
case 2:
thirdSlot = "Plums";
break;
case 3:
thirdSlot = "Bells";
break;
case 4:
thirdSlot = "Melons";
break;
case 5:
thirdSlot = "Bars";
break;
}
System.out.println ("\n-------------------------------");
System.out.printf ("%-12s%-10s%5s\n", firstSlot , secondSlot , thirdSlot);
System.out.print ("\n-------------------------------");
//check how many of the slots match to calculate the winnings
if (slot1 == slot2 && slot1 == slot3)
{
winnings = bet * 3;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 3. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
else if ((slot1 == slot2 && slot2 != slot3) || (slot1 == slot3 && slot1 != slot2) || (slot2 == slot3 && slot3 != slot1))
{
winnings = bet * 2;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 2. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
else
{
winnings = bet * 0;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 0. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
} while ((bet > 0) && (money > 0));
FileWriter fwriter = new FileWriter("scores.txt", true);
PrintWriter outputWriter = new PrintWriter(fwriter);
outputWriter.printf("\n\n%1s%15s" , "Name" , "Score");
outputWriter.printf ("\n\n%1s%15s" , "----" , "-----");
outputWriter.printf ("\n\n%1s%15s" , username , score);
outputWriter.close();
System.out.println("\n\nGame over! Your score has been written to scores.txt, " + username + "!");
} //end of actions for select option 1
//option 2 user wants to read their scores
if (option == 2)
{
File myFile = new File("scores.txt");
//if there are no scores to read
if (!myFile.exists())
{
System.out.println("There are no scores to display at this time.");
continue;
}
File file = new File("scores.txt");
Scanner inputFile = new Scanner(file);
while (inputFile.hasNext())
{
String username = inputFile.nextLine();
System.out.println(username);
}
inputFile.close();
} //close option 2
} while (option != 3); //close 1st do-while loop
if (option == 3)
{
System.out.print ("\nGoodbye!");
System.exit(0);
}
}
}
答案 2 :(得分：-1)
Int counter = 0, input = 0;
While(counter < 10 && input = 0)
{
Thread.sleep(1000);
Counter++;
input = Scan.nextInt()
}
不是我用手机做过的最好的代码，所以