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Basic Java HiLow guessing game

I am fully aware this question has been asked many times, it is a classic first year problem in CSC. I am not looking for the solution to the problem itself. I think I have it basically done however I am missing something that I cannot find how to do.
Here is my code:
import java.util.Scanner;
import java.util.Random;
public class HiLow
{
public static void main (String[] args)
{
Random generator = new Random();
Scanner scan = new Scanner(System.in);
int num1,guess;
int count = 0;
num1 = generator.nextInt(100) + 1;
while(true) {
System.out.print("Enter an integer between 1 or 100 or enter 0 at anytime to quit: ");
guess = scan.nextInt();
count++;
if(guess == num1 || guess == 0) {
if(guess == 0) {
System.out.println("Thanks for playing");
break;
}
System.out.println("Congrats you've guessed correct and your total guesses is " + count );
break;
}
else if (guess > 100 || guess < 1) {
System.out.print("I see you cannot follow instructions. I said ");
count--;
}
else if (guess > num1) {
System.out.println("You have guessed too high. ");
}
else {
System.out.println("You have guessed too low.");
}
}
}
}
My problem is i am required to prompt the user at the point of "if the user quits or successfully guesses the correct number, prompt the user to see if they wish to play again". I am lost and not sure how to continue my while loop from the beginning after my breaks. Is there a way to end the break condition i have from (guess == num1 || guess ==0) and direct my program to start again at the while(true) statement?
Thanks

I will say search up continue;
Tips to help further:
The continue statement is used to bring the loop back to the start, try it instead of a break where you want the user to continue.
You need some sort of check if the user wants to continue, (try asking them to type in some specific int you check, p.s negative numbers are integers as well)

#Ahmed thinks you should continue, I would rather not break, or conditionally break.

Well there are multiple ways you could accomplish this, One would be to just to prompt the user with a "press q to quit" dialogue using the Scanner class where .next() returns the String when the user hits enter:
if(guess == num1 || guess == 0) {
if(guess == 0) {
System.out.println("Thanks for playing");
}else{
System.out.println("Congrats you've guessed correct and your total guesses is " + count );
}
System.out.println("would you like to play again [y/n]?");
if(scan.next().equals("y")){
num1 = generator.nextInt(100) + 1;
count=0;
}else{
break;
}
}
If thats what you mean. Hopefully I helped.
or maybe you can have it only quit at zero, if so just remove that second break and replace it with num1 = generator.nextInt(100) + 1; to set the new value to guess.

While loop NoSuchElementException integer input java

I'm having some trouble with a menu program I am writing for my java class. After one program is run, when the program goes to do a second loop it throws a NoSuchElementException on the line where it is supposed to take the user's input for the next program they want to run. I'm assuming it has something to do with the scanner getting messed up but I can't find the issue. Anyone have any ideas?
public static void main(String[] args) {
Scanner console = new Scanner(System.in);
String pin;
int selection = 0;
boolean valid = false;
do {
System.out.print("Please enter the password: ");
pin = console.nextLine();
valid = checkPassword(pin);
} while (!valid);
while (selection != 4 && valid == true) {
System.out.printf("%nPlease select a number from the menu below %n1: Wage "
+ "Calculator 2: Tip Calculator 3: Grocery Discount 4: Exit %n");
selection = console.nextInt();
if (selection == 1) {
calc_wages();
} else if (selection == 2) {
calc_tip();
} else if (selection == 3) {
System.out.print("We haven't gotten this far yet");
} else if (selection == 4){
System.out.print("Thank you for using the program.");
break;
} else {
System.out.print("There is no option for what you entered. Try again");
}
selection = 0;
}
}//main

Your code so far is fine.
From what you're saying the problem starts after the user makes a selection.
In calc_wages() and/or calc_tip() it's possible that you use another Scanner object to get the user's input.
This is a source of problems.
Declare 1 Scanner object at the class level and use it throughout you code and close it only when it is no longer needed.

Reading input using Scanner causes an infinite loop in Java [duplicate]

This question already has answers here:
How to handle infinite loop caused by invalid input (InputMismatchException) using Scanner
(5 answers)
Closed 5 years ago.
In my program I'm trying to get a user to input an int between 1-3 and then do something based off what they type. If it is not a number or not one of the options then it will allow them to reenter a valid option.
The issue I have is I'm having trouble brainstorming how to not have it infinitely loop and just allow them to enter in a number after the console tells them they entered an invalid input.
int i = 0;
while (i < 1) {
try {
int level = scan.nextInt();
i+=1;
if (level == 1) {
System.out.println("You selected level 1!");
//Start the game
} else if (level == 2) {
System.out.println("You selected level 2!");
//Start the game
} else if (level == 3) {
System.out.println("You selected level 3!");
//Start the game
} else {
System.out.println("That's not an option!");
i-=1;
}
} catch(InputMismatchException input) {
System.out.println("That's not an option!");
i-=1;
}
}

When you input an invalid input, you need to clear it. Add scan.next() when input exception triggered so as to clear it with next():
catch(InputMismatchException input) {
System.out.println("That's not an option!");
scan.next();
i-=1;
}

Not quite the answer you were expecting, but: refactor this code. Remember the basics of java, where every functional bit has its own method. So use a method that reads the input, and returns the level selected (or -1 if nothing):
int readInput() {
// your code here, returning either the level or -1 on bad input
}
And then call that for your read loop:
int selected;
do {
selected = readInput();
} while(selected < 1);

You are better off writing the code like this:
while(true){
try{
int level = scan.nextInt();
if(level==1){
System.out.println("You selected level 1!");
break;
}else if(level==2){
System.out.println("You selected level 2!");
break;
}else if(level==3){
System.out.println("You selected level 3!");
break;
}else{
System.out.println("That's not an option!");
continue;
}
}catch(InputMismatchException input){
System.out.println("That's not an option!");
continue;
}
}
continue will immediately resume execution of the loop at the top, and break will immediately jump too the closing brace } of the while. This removes the use of the i counter variable, which was entirely useless to the code. Also, this code will never run indefinitely, unless the user indefinitely enters improper values!
Hope this helped, good luck!

You can proceed in a much simpler way. The 3 valid cases are very similar and can be treated as one, the game can be started only once after the loop because we know that once the loop exits, level has a valid value.
boolean valid = false;
int level;
do {
try {
level = scan.nextInt();
valid = 1 <= level && level <= 3;
if (valid) {
System.out.println(String.format("You selected level %d !",level));
} else {
System.out.println("That's not an option!");
}
} catch(InputMismatchException input) {
scan.next();
System.out.println("That's not an option!");
}
} while (!valid);
// start the game

Infinite looping; do not understand how

In the code below, when I input anything other than an integer value the code does not ask for my input again and just loops the string outputs infinitely. A little help...
int choice = 0;
while(choice == 0)
{
try
{
System.out.println("Start by typing the choice number from above and hitting enter: ");
choice = input.nextInt();
}
catch(Exception e)
{
}
if ((choice == 1) || (choice == 2) || (choice == 3))
{
break;
}
else
{
System.out.println("Invalid choice number. Please carefully type correct option.");
choice = 0;
}
}

When you input a non-integer it will not be consumed. You need to scan past it. This can be done by, for example, adding a input.nextLine() statement to your catch block. This will consume the invalid input and allow your program to read new data.
This will solve your problem:
catch(Exception e)
{
input.nextLine(); // Consume the invalid line
System.out.println("Invalid choice number. Please carefully type correct option.");
}
You could also read the line as a string and try to parse it as a number using Scanner.nextLine and Integer.parseInt, but I prefer using nextInt for integers. It makes the purpose of the code more clear (in my opinion).

When nextInt is used and the next input is not an int, it will throw an exception but not consume the data, i.e. the next call will return immediately because the data is still present.
You can fix this by calling the skip method with a pattern like [^0-9]* to skip all invalid input. Then an input like "aaa3" would work. If you want to ignore everything, use .* as pattern.

The trouble is that you are not consuming the remaining data in the stream. I solved it with the following code, although you will want to document you code better before you use it in a program:
int choice = 0;
while(choice == 0)
{
try
{
System.out.print("Start by typing the choice number from above and hitting enter: ");
choice = input.nextInt();
}
catch(Exception e)
{
input.next();
System.out.println("Invalid choice number. Please carefully type correct option.");
}
if ((choice == 1) || (choice == 2) || (choice == 3))
{
break;
}
choice = 0;
}

You can simplify and reduce your code as follows:
int choice;
System.out.println("Start by typing the choice number from above and hitting enter: ");
while(true)
{
try {
choice = input.nextInt();
if ((choice == 1) || (choice == 2) || (choice == 3))
break;
} catch(InputMismatchException e) { // handle only the specific exception
input.nextLine(); // clear the input
}
System.out.println("Invalid choice number. Please carefully type correct option.");
}

Are you using Scanner(system.in); from the import java.util.Scanner; package?
Try adding input.nextLine(); in the catch to clear the value to stop the infinite loop.
public static void main(String[] args) {
int choice = 0;
Scanner input = new Scanner(System.in);
while(choice == 0)
{
try
{
System.out.println("Start by typing the choice number from above and hitting enter: ");
choice = input.nextInt();
}
catch(Exception e)
{
input.nextLine();
System.out.println("Invalid choice number. Please carefully type correct option.");
}
if ((choice == 1) || (choice == 2) || (choice == 3))
{
break;
}
else
{
System.out.println("Invalid choice number. Please carefully type correct option.");
choice = 0;
}
}
}

Looks like in the line choice = input.nextInt();
choice value is always 0. Print choice soon after that.
Also for non integer value add a condition to break from the loop.

Syntax error on token "else", delete this [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking for code must demonstrate a minimal understanding of the problem being solved. Include attempted solutions, why they didn't work, and the expected results. See also: Stack Overflow question checklist
Closed 9 years ago.
Improve this question
I keep on getting this error and I tried mixing it around. But then when I choose the option, it does the option, but then said "you did not enter 1, 2 or 3".
This is the the full code. How to fix it?
The error is at
} else {
System.out.println("You did not enter 1, 2 or 3");
} else {
System.out.println("The Pin You Entered Was Wrong");
}

This is an incorrect syntax:
}else{
System.out.println("You did not enter 1, 2 or 3");
}else{
System.out.println("The Pin You Entered Was Wrong");
Just do it this way:
else {
System.out.println("You did not enter 1, 2 or 3");
System.out.println("The Pin You Entered Was Wrong");
}

The problem is in the code you provided on your paste bin.
You use two else statements, so Java complains as it doesn't know which to go to after the initial if statement.
You need to enter in another conditional statement using else if, then else. For example:
if (option == 1){
Option_1 Optionone = new Option_1();
Optionone.Withdraw();
}
etc
}else if (nothing entered) {
System.out.println("You did not enter 1, 2 or 3");
}else{
System.out.println("The Pin You Entered Was Wrong");
}
You also have another major problem with your code. You declare the variable option and set it in an if statement, so it only has scope within that if statement. You then come out of the if statement and declare a brand new option variable before the code I provided above. This will not function, as the option integer has no value.
Instead, you need to declare your initial option int outside of your if statement, like so:
int number;
int password = 7123;
int amount = 4000;
int option;
if (number == password) {
etc...
option = userInput.nextInt();
}
Furthermore, you come out of the if statement checking the entered number against the stored password to take input on withdrawing cash etc. This is no good. It means that after the if statement checking number against password is finished, it will automatically proceed to the next block of code.
As the scanner object hasn't been created, the first three if statements will come back false and your else statement will be printed (regardless of whether the input password was correct).
Therefore, I would advise you to put that check in a separare else statement and use a while loop to confirm a correct selection ahs been entered. For example:
System.out.println("Please Enter Your Bank Pin.");
Scanner userInput = new Scanner (System.in);
int number;
int password = 7123;
int amount = 4000;
int option;
number = userInput.nextInt();
if (number == password) {
System.out.println("Pin Accepted");
System.out.println("You Have Now Entered Harry's Bank!");
System.out.println("Press The Number Of The Option You Would Like.");
System.out.println("1.Withdraw Money.");
System.out.println("2.Put In Money");
System.out.println("3.Exit Bank");
Scanner Options = new Scanner (System.in);
option = userInput.nextInt();
while (option != 1 || option != 2 || option != 3) {
System.out.println("You didn't enter a valid number. Try again");
option = userInput.nextInt();
}
if (option == 1){
Option_1 Optionone = new Option_1();
Optionone.Withdraw();
}
else if (option == 2){
Option_2 Optiontwo = new Option_2();
Optiontwo.Deposit();
}
else if (option == 3){
Option_3 Optionthree = new Option_3();
Optionthree.Exit();
}
}
else
System.out.println("The Pin You Entered Was Wrong");
}

your second else statement does not close no if statement.
Also, the option variable is not in the right scope:
try this
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
System.out.println("Welcome To Harry's Bank");
//Pin System
System.out.println("Please Enter Your Bank Pin.");
Scanner userInput = new Scanner (System.in);
int number;
int password = 7123;
int amount = 4000;
number = userInput.nextInt();
int option;
if (number == password) {
System.out.println("Pin Accepted");
System.out.println("You Have Now Entered Harry's Bank!");
System.out.println("Press The Number Of The Option You Would Like.");
System.out.println("1.Withdraw Money.");
System.out.println("2.Put In Money");
System.out.println("3.Exit Bank");
Scanner Options = new Scanner (System.in);
option = userInput.nextInt();
}else{
System.out.println("The Pin You Entered Was Wrong");
}
if (option == 1){
Option_1 Optionone = new Option_1();
Optionone.Withdraw();
}
if (option == 2){
Option_2 Optiontwo = new Option_2();
Optiontwo.Deposit();
}
if (option == 3){
Option_3 Optionthree = new Option_3();
Optionthree.Exit();
}else{
System.out.println("You did not enter 1, 2 or 3");
}
}
}

The problem is that you the 'else' statement twice in your if-else construct.
You have:
if { }
else { }
else { }
But you probably want:
if { }
else if { }
else { }

You cannot have TWO else in a if-else case.
Your nested If statement is not proper. Use it as below
if (number == password) {
.....
.....
if (option == 1) {
}
else if (option == 2) {
}
else if (option == 3) {
} else {
System.out.println("You did not enter 1, 2 or 3");
}
} else {
System.out.println("The Pin You Entered Was Wrong");
}

You can't have two else blocks added to an if
} else {
System.out.println("You did not enter 1, 2 or 3");
} else {
System.out.println("The Pin You Entered Was Wrong");
}
Either drop one or club the two println()s into one else block
} else {
System.out.println("You did not enter 1, 2 or 3");
System.out.println("The Pin You Entered Was Wrong");
}
Take a look at how to use the if-then and if-then-else statements.
Alternatively, I suggest you to make use of the Switch statements for better clarity of code.
switch (option) {
case 1: Option_1 OptionOne = new Option_1();
OptionOne.Withdraw();
break;
case 2: Option_2 OptionTwo = new Option_2();
OptionTwo.Withdraw();
break;
case 3: Option_3 OptionThree = new Option_3();
OptionThree.Withdraw();
break;
default: System.out.println("You did not enter 1, 2 or 3");
System.out.println("The Pin You Entered Was Wrong");
}