I am trying to create a while loop where the user has a total of three tries to enter a valid number. I'm not understanding how the system recognizes that 3 invalid attempts have been made before displaying the message.
Classes, variables, and scanner objects are made. After the three attempts, I want to say "No more tries". I already have the program written to use the user's input for quantity if its valid. This is just if they input three invalid attempts.
Updated code:
int quantity = 0;
// Get user's desired amount of lemonade cups
System.out.print("Hello " + name + ". How many cups of lemonade can I get you? ");
quantity = keyboard.nextInt(); // Store amount of cups wanted
int attempts = 0;
int maxAttempts = 3;
double subTotal = quantity * lemonadeCost;
double totalTax = subTotal * 0.08;
double totalPrice = subTotal + totalTax;
while (attempts < maxAttempts) {
if (quantity < 1 || quantity >= 20) {
System.out.println("That is an invalid amount, please try again");
quantity = keyboard.nextInt(); }
else {
System.out.println("Subtotal: " + defaultFormat.format(subTotal));
System.out.println("Tax: " + defaultFormat.format(totalTax));
System.out.println("Total: " + defaultFormat.format(totalPrice));
}
attempts++;
if (attempts >= 3) {
System.out.print ("No lemonade for you");
break;
}
// Ask for user's payment method
Scanner method = new Scanner(System.in);
System.out.println("How would you like to pay? Enter 'm' for money, 'c' for credit or 'g' for gold. ");
String payment = method.nextLine();
dxdy is correct about the braces required for making the while() loop function.
Once the while loop has ended (either quantity is between 1 and 20, or attempts > maxAttempts), you just need to have an if statement like the following:
if (attempts > maxAttempts) {
System.out.println("No more tries);
return -1; // or something else to break out of your code
}
and then continue on with the rest of your code working with the quantity variable.
You seem to be missing the opening and closing brackets for the loop. As it is, your code reads
while (quantity < 1 || quantity >= 20 && attempts <= maxAttempts)
System.out.println("That is an invalid amount, please try again");
// these below are not part of the loop
quantity = keyboard.nextInt();
attempts++;
Instead you should do
while (quantity < 1 || quantity >= 20 && attempts <= maxAttempts){
System.out.println("That is an invalid amount, please try again");
quantity = keyboard.nextInt();
attempts++;
}
try this code:
//start with 1 since the user will attempt it at least one time.
int attempts = 1;
int maxAttempts = 3;
int quantity=0;
Scanner keyboard = new Scanner(System.in);
//LESS THAN OR EQUAL TO 3...
while(attempts<=maxAttempts){
System.out.print("Enter amount: ");
quantity = keyboard.nextInt();
//check if valid
if(quantity < 1 || quantity >= 20){
//check if it's 1st and 2nd trial.
if(attempts<maxAttempts){
System.out.println("That is an invalid amount, please try again");
}else{
//third trial and still invalid
System.out.print("No more tries");
}
}else{
//user entered a valid amount so let's break the loops.
System.out.println("The amount is valid. Value of amount: "+ quantity);
break;
}
//increment attempts
attempts++;
}
//never forget to close the scanner
keyboard.close();
}
}
Though I could have turned this into methods if it's allowed
EDIT: As you updated the question, so it was necessary to update the answer too. Here it is what you actually want.
public static void main(String[] args) {
// Get user's desired amount of lemonade cups
String name = "Jimmy Nguyen";
Scanner keyboard = new Scanner(System.in);
int quantity;// Store amount of cups wanted
int lemonadeCost = 4; // Suppose
int attempts = 0;
int maxAttempts = 3;
System.out.print("Hello " + name + ". How many cups of lemonade can I get you? ");
while (attempts < maxAttempts) {
quantity = keyboard.nextInt();
if (quantity < 1 || quantity >= 20) {
System.out.println("That is an invalid amount, please try again\n");
++attempts;
} else {
double subTotal = quantity * lemonadeCost;
double totalTax = subTotal * 0.08;
double totalPrice = subTotal + totalTax;
System.out.println("Subtotal: " + subTotal);
System.out.println("Tax: " + totalTax);
System.out.println("Total: " + totalPrice);
// Ask for user's payment method
System.out.println("How would you like to pay? Enter 'm' for money, 'c' for credit or 'g' for gold. ");
keyboard.nextLine();
String payment = keyboard.nextLine();
break;
}
if (attempts >= 3) {
System.out.print("No lemonade for you");
break;
}
}
}
Related
I have an application that acts as a gradebook. However, in the console log when I type in a grade there seems to be an error. I was hoping someone could fix this to where I am able to put in a grade percentage and the error does not pop up.enter code here
Below is what the error says:java.lang.NumberFormatException: For input string: "70%"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at Gradebook.getScores(Gradebook.java:45)
at Gradebook.main(Gradebook.java:154)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)
Here is my code:
import java.util.Scanner;
public class Gradebook {
//getNumStudents takes a Scanner object as parameter
//the reader object lets us take user input
public static int getNumStudents(Scanner reader){
int numStudents = 0;
//we get the number of students
do{
System.out.print("Enter number of students: ");
numStudents = Integer.parseInt(reader.nextLine());
//we determine if the user input is valid
//it should be greater than 0
//because we don't want the number o students to be negative
//if it is not valid then we keep taking inputs
if(numStudents > 0){
break;
}else{
System.out.println("Please enter atleast 1 student.");
}
}while(true);
System.out.println("================================================================================================================================================");
//we return numStudents
return numStudents;
}
//getScores takes our Scanner object again and the number student as parameter this time
public static String[] getScores(Scanner reader, int numStudents){
//we create an array of string studInfo
//that will be returned containing the name, and scores of our students
String[] studInfo = new String[numStudents];
String name = "";
int quiz = 0;
int assign = 0;
int test1 = 0;
int test2 = 0;
//we use a for loop to keep taking student scores
for(int i = 0; i < numStudents; i++){
//enter name
System.out.print("Enter student "+(i+1)+" name: ");
name = reader.nextLine();
//enter quiz, assignment, test1 and test2 scores
//we also validate scores to not be negative
//and not out of bounds
do{
System.out.print("Enter Quiz Score (over 40): ");
quiz = Integer.parseInt(reader.nextLine());
if(quiz >= 0 && quiz <= 40){
break;
}else{
System.out.println("Please put a valid score.");
}
}while(true);
do{
System.out.print("Enter Assignment Score (over 30): ");
assign = Integer.parseInt(reader.nextLine());
if(assign >= 0 && assign <= 30){
break;
}else{
System.out.println("Please put a valid score.");
}
}while(true);
do{
System.out.print("Enter Midterm Test Score (over 55): ");
test1 = Integer.parseInt(reader.nextLine());
if(test1 >= 0 && test1 <= 55){
break;
}else{
System.out.println("Please put a valid score.");
}
}while(true);
do{
System.out.print("Enter Final Test Score (over 65): ");
test2 = Integer.parseInt(reader.nextLine());
if(test2 >= 0 && test2 <= 65){
break;
}else{
System.out.println("Please put a valid score.");
}
}while(true);
//after we get the name and student's score
//we put it in a string
studInfo[i] = name+ " " +quiz+ " " +assign+ " " +test1+ " " +test2;
System.out.println();
}
//return the studInfo
return studInfo;
}
//our displayGrade takes String array as parameter
public static void displayGrade(String[] studInfo){
//this is our header for our formatted table
System.out.println("================================================================================================================================================");
System.out.println(String.format("%-30s%-10s%-12s%-15s%-12s%-10s%-15s%s", "Name", "Quiz", "Assignment", "Midterm Test", "Final Test", "Average", "Letter Grade", "Status"));
System.out.println("================================================================================================================================================");
//we go through our array of string
for(int i = 0; i < studInfo.length; i++){
//the split method returns an array of strings
//that are split by a delimeter
String[] data = studInfo[i].split(" ");
//we sum up the scores
//but we have to parse it to double first
//to get the closest sum
double sum = ((Double.parseDouble(data[1]) / 40.0) * 100.0) * 0.15;
sum += ((Double.parseDouble(data[2]) / 30.0) * 100.0) * 0.15;
sum += ((Double.parseDouble(data[3]) / 55.0) * 100.0) * 0.3;
sum += ((Double.parseDouble(data[4]) / 65.0) * 100.0) * 0.4;
//after that we round the sum and convert it to int and put it in average
int average = (int) Math.round(sum);
char letterGrade = ' ';
//we get the letter grade using a nested if else
if(average>=0 && average<=59){
letterGrade = 'F';
}else if(average>=60 && average<=69){
letterGrade = 'D';
}else if(average>=70 && average<=79){
letterGrade = 'C';
}else if(average>=80 && average<=89){
letterGrade = 'B';
}else if(average>=90 && average<=100){
letterGrade = 'A';
}
String status = "";
//we determine the status of our student here
//using switch case
//if the leter grade is f then he fails
//if the case is D then he needs to go to remedial class
//otherwise they pass
switch(letterGrade){
case 'F':
status = "Fail";
break;
case 'D':
status = "Remedial";
break;
case 'A': case 'B': case 'C':
status = "Pass";
break;
}
//we displat student information
System.out.println(String.format("%-30s%-10s%-12s%-15s%-12s%-10d%-15c%s", data[0], data[1], data[2], data[3], data[4], average, letterGrade, status));
}
System.out.println("================================================================================================================================================");
}
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
displayGrade(getScores(reader, getNumStudents(reader)));
}
}
Instead of nextLine() you can use next("[0-9]+%?") and then remove the optional % character:
public static int getNumStudents(Scanner reader) {
int numStudents = 0;
//we get the number of students
do {
System.out.print("Enter number of students: ");
// Read the number either with or without the % sign
String input = reader.next("[0-9]+%?");
if (input.endsWith("%")) {
// Remove the % sign if present
input = input.substring(0, input.length() - 1);
}
numStudents = Integer.parseInt(input);
// we determine if the user input is valid
// it should be greater than 0
// because we don't want the number o students to be negative
// if it is not valid then we keep taking inputs
if (numStudents > 0) {
break;
}
System.out.println("Please enter at least 1 student.");
} while (true);
System.out.println("================================================================================================================================================");
// we return numStudents
return numStudents;
}
this project i use do while loop with switch case to check the input case is not match or not. i run the code but the result not what i wanted. what i expect is if the user type the wrong case, the do while loop will loop back to the input where user need to enter the case.
here is the code
package vending.machine;
import java.util.Scanner;
import java.util.*;
import java.util.ArrayList;
import static vending.machine.adddrinks.drinksList;
public class VendingMachine {
public static void main (String []args){
Scanner sc= new Scanner(System.in);
double money;
double total;
double balance;
do{
System.out.println("\nPlease insert money:");
money = sc.nextDouble();
if(money < 1.2){
System.out.println("Not enough money");
}
}while(money < 1.2);
System.out.println("What drinks are you looking for");
adddrinks.showDrinks();
adddrinks.viewDrinks();
System.out.print("Select: 1 or 2 or 3 or 4\n");
int select=sc.nextInt();
do{
switch(select){
case 1:{
total = adddrinks.drinksList.get(0).getdrinkPrice();
balance = money - total;
System.out.println("Here is your balance: " + balance);
break;
}
case 2:{
total = adddrinks.drinksList.get(1).getdrinkPrice();
balance = money - total;
System.out.println("Here is your balance: " + balance);
break;
}
case 3:{
total = adddrinks.drinksList.get(2).getdrinkPrice();
balance = money - total;
System.out.println("Here is your balance: " + balance);
break;
}
case 4:{
total = adddrinks.drinksList.get(3).getdrinkPrice();
balance = money - total;
System.out.println("Here is your balance: " + balance);
break;
}
default:{
System.out.println("Invalid");
break;
}
}
}while(select<5);
}
}
here is the result
enter image description here
From what I understood from your code. When you are giving the input as 5 it is giving invalid.
After that it will go to the while statement and check the condition there. If you are inside the switch case and select any random case It will show you invalid. After that depending upon the number that you have entered.
If the number is less than 5, It will again go to switch case.
As it doesn't make sense as If you continue to provide correct input to it. The code will continue to execute making the balance going in the negative. this condition should be changed to
while(balance>1.2)
assuming that it is minimum amount that is necessary to buy a drink. This will check the condition after every drink and will hopefully do what you were hoping.
On side Note : Make your code modular.
You need to loop over your input, i was so free to improve your code a bit (sorry I do not like repetations):
private static void main10(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("What drinks are you looking for");
adddrinks.showDrinks();
adddrinks.viewDrinks();
int select = 0;
double balance = 0;
boolean running = true;
while (running) {
if (sc.hasNextInt()) {
select = sc.nextInt();
if (0 < select && select <= adddrinks.drinksList.size()) {
double price = adddrinks.drinksList.get(select - 1).getdrinkPrice();
if (balance < price) {
System.out.println("Not enough money, " + select + " costs " + price);
} else {
balance -= price;
System.out.println("You choosed " + select + " , you will find it in the dispenser");
}
} else {
System.out.println("Invalid input, please retry");
}
} else if (sc.hasNextDouble()) {
balance += sc.nextDouble();
} else {
String input = sc.next();
if (input == "q") {
running = false;
if (0 < balance)
System.out.println("please don't forget your change with amount of: " + balance);
System.out.println("Have a nice day, happy to see you again");
break;
} else if (input == "h") {
System.out.println("What drinks are you looking for");
adddrinks.showDrinks();
adddrinks.viewDrinks();
} else {
System.out.println("Invalid input, please retry");
}
}
System.out.println("Your balance is: " + balance);
System.out.println(
"please chouce your product (e.g 2), enter coins (e.g 2.0), click on 'h' to show product list or click on 'q' to get your change");
}
}
so I have another homework question. First, I'll list the instructions and then I'll list my code and hopefully someone can help me/guide me in the right direction.
DIRECTIONS:
Write a program that calculates the occupancy rate for a hotel. The program should start by asking the user how many floors the hotel has. A for loop should then iterate once for each floor. In each iteration of the for loop, the program should ask the user for the number of rooms of the floor and how many of them are occupied. After all of the iterations are complete the program should display how many rooms the hotel has, how many of them are occupied, and the percentage of rooms that are occupied.
It is traditional that many hotels do not have a 13th floor. The for loop in >this program should skip the entire thirteenth loop iteration.
Input validation (remember to use a loop never ever an "if"): Do not accept a value of less than one for the number of floors. Do not accept a value of less than 10 for the number of rooms on a floor.
MY CODE:
import java.util.Scanner;
import java.text.DecimalFormat;
public class Homework7Hotel
{
public static void main (String[] args)
{
Scanner keyboard = new Scanner (System.in);
DecimalFormat formatter = new DecimalFormat("%#,##0.00");
int numFloors = 0;
int numRooms = 0;
int totalRooms = 0;
int numOccupied = 0;
int totalOccupied = 0;
int percentOccupied = 0;
System.out.println("Please enter the number of floors in the hotel: ");
numFloors = keyboard.nextInt();
while (numFloors <1)
{
System.out.println("You have entered an invalid number of floors. ");
System.out.println("Please enter the number of floors in the hotel: ");
numFloors = keyboard.nextInt();
}
for (int counter = 1; counter <=numFloors; counter++)
{
System.out.println("Please enter the number of rooms on floor #: " + counter);
numRooms=keyboard.nextInt();
totalRooms += numRooms;
while (numRooms <10)
{
System.out.println("You have entered an invalid number of rooms. ");
System.out.println("Please enter the number of rooms on floor #: " + counter);
numRooms = keyboard.nextInt();
}
System.out.println("Please enter the number of occupied rooms on floor #: " + counter);
numOccupied = keyboard.nextInt();
totalOccupied += numOccupied;
// *not sure of how to do this* percentOccupied = totalOccupied/totalRooms;
}
System.out.println("The hotel has a total of " + totalRooms + " rooms.");
System.out.println(totalOccupied + " of the rooms are occupied.");
System.out.println (percentOccupied + "% of the rooms are occupied.");
}
}
So, the issue I am having is:
1) As per the instructions, how would I skip the 13th floor entirely in the loop?
Any help would be greatly appreciated! Thank you!
You could use a continue keyword in a forloop like.
for(int i = 0;i <20;i++){
if(i == 13){
continue;
}
//Do rest of your steps
}
If you donot want to use continue use
for(int i = 0;i <20;i++){
if(i != 13){
//Do rest of your steps
}
//This should also work it will not do anything when loop is at its 13th iteration.
}
Using continue though is better.
public static void main (String[] args)
{
Scanner keyboard = new Scanner (System.in);
DecimalFormat formatter = new DecimalFormat("%#,##0.00");
int numFloors = 0;
int numRooms = 0;
int totalRooms = 0;
int numOccupied = 0;
int totalOccupied = 0;
int percentOccupied = 0;
System.out.println("Please enter the number of floors in the hotel: ");
numFloors = keyboard.nextInt();
while (numFloors <1)
{
System.out.println("You have entered an invalid number of floors. ");
System.out.println("Please enter the number of floors in the hotel: ");
numFloors = keyboard.nextInt();
}
for (int counter = 1; counter <=numFloors; counter++)
{
System.out.println("Please enter the number of rooms on floor #: " + counter);
numRooms=keyboard.nextInt();
//REMOVE totalRooms += numRooms; from here
while (numRooms <10)
{
System.out.println("You have entered an invalid number of rooms. ");
System.out.println("Please enter the number of rooms on floor #: " + counter);
numRooms = keyboard.nextInt();
}
totalRooms += numRooms; //ADD it here
System.out.println("Please enter the number of occupied rooms on floor #: " + counter);
numOccupied = keyboard.nextInt();
totalOccupied += numOccupied;
// *not sure of how to do this* percentOccupied = totalOccupied/totalRooms;
}
System.out.println("The hotel has a total of " + totalRooms + " rooms.");
System.out.println(totalOccupied + " of the rooms are occupied.");
System.out.println (percentOccupied + "% of the rooms are occupied.");
}
Without continue, you can try if() else block to do the work.
for(int i = 0; i < 20; i++)
{
if(i == 13)
{
// Do the stuff for 13th floor if any
}
else
{
// Do the stuff for floors other than 13
}
}
I am trying to prompt the user if the information they entered is correct and the program just proceeds anyway instead of re-prompting the user. I think i need to change how I loop this do some type of do-while loop, but I don't quite know what to do.
{
//Here we will set up our method of data entry and decimal format
Scanner keyboard = new Scanner(System.in);
DecimalFormat eNotation1 = new DecimalFormat("00.00");
//Let's introduce our program to the user
System.out.println("Hi, This is a program to calculate quarterly interest growth");
//Here we will prompt the user to enter the amount of quarters
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
int quarterNumber = keyboard.nextInt();
if (quarterNumber > 10 || quarterNumber < 0)
{
System.out.println("You entered a number outside of the boundrys. Please run the program again and choose a number between 0 and 10 (number can include 10)");
System.exit(0);
}
//Here we will prompt the user for the starting balance.
System.out.println("What is the starting balance of this account?");
double startingBalance = keyboard.nextDouble();
//Here we will prompt the user for the interest rate
System.out.println("What is the interest rate (in percent) in your area? Please pick a number from 1 - 20.");
double interestRate = keyboard.nextDouble();
if (interestRate < 1 || interestRate > 20)
{
System.out.println("You entered a number outside of the boundrys. Please run the program again and choose a number between 1 and 20 (can include 1 and 20)");
System.exit(0);
}
//Here we will double check with the user that the info is correct.
System.out.println("The amount of quarters you would like displayed is " + quarterNumber);
System.out.println("The starting balance you would like to work with is " + startingBalance);
System.out.println("The interest rate in your area is " + interestRate);
System.out.println("Is this information correct?");
keyboard.nextLine();
String answer = keyboard.nextLine();
System.out.println("");
//We will have them enter the information again if the answer is no or No
if (answer == "no" || answer == "No")
{
//Here we will prompt the user to enter the amount of quarters
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
keyboard.nextInt();
quarterNumber = keyboard.nextInt();
//Here we will prompt the user for the starting balance.
System.out.println("What is the starting balance of this account?");
keyboard.nextDouble();
startingBalance = keyboard.nextDouble();
//Here we will prompt the user for the interest rate
System.out.println("What is the interest rate (in percent) in your area? Please pick a number from 1 - 20.");
keyboard.nextDouble();
interestRate = keyboard.nextDouble();
}
//Next we will proceed with the calculation if the information is indeed correct
double endingBalance = startingBalance + (startingBalance * (interestRate / 100 * .25));
double interestEarned = endingBalance - startingBalance;
//Now we will output the information
for (int qn = 1; qn < (quarterNumber + 1); qn++ , startingBalance = startingBalance + interestEarned , endingBalance =startingBalance + (startingBalance * (interestRate / 100 * .25)), interestEarned = endingBalance - startingBalance )
{
System.out.println("Quarter Number Starting Balance Interest Earned Ending Balance ");
System.out.println(qn + " " + eNotation1.format(startingBalance) + " " + eNotation1.format(interestEarned) + " " + eNotation1.format(endingBalance) + " ");
}
}
}
I probably figured what your problem is.
Example code snippet: (Note I am doing without an actual java editor so just handle any missing syntax
//Here we will prompt the user to enter the amount of quarters
int quarters = 0;
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
do
{
quarters = keyboard.nextInt();
if (quarters <= 0 || quarters >= 10)
{
System.out.println("You entered a number outside of the boundrys. Please Type a number greater than 0 and less than equal to 10 again)");
}
}
while (quarters <= 0 || quarters >= 10)
The idea is for a recursive prompt. The application first prompts the user to type in the result, and then you handle the amount of So you have to handle the prompt within the do-while loop. Assuming you don't want to repeat the same old text, you can do what I did (which is much cleaner in my opinion).
EDIT: Assuming you want to handle the entire repeating of the application. place everything for the declaration of variables into a method (or better various methods for cleaner handling, and handle something like this.
int quarters;
double balance;
//TODO : Add all other required variables
string verification;
do
{
quarters = getNumberOfQuartersFromUser();
balance = getStartingBalance();
... //TODO : all the other methods
//verification
System.out.println("Is this accepted?");
verification = keyboard.nextString();
//Handle verfication if it is no or No
if (verification == null || verification == "No" || verification == "no")
{
System.out.println("Starting from the beginning again");
}
}
while (verification == null || verification == "No" || verification == "no")
//out of loop, so handle calculation.
...
and a method snippet
private int getNumberOfQuartersFromUser()
{
int quarters = 0;
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
do
{
quarters = keyboard.nextInt();
if (quarters <= 0 || quarters >= 10)
{
System.out.println("You entered a number outside of the boundrys. Please Type a number greater than 0 and less than equal to 10 again)");
}
}
while (quarters <= 0 || quarters >= 10)
return quarters;
}
I think you should enclose your codes to Else statement to avoid proceeding unintentionally. Remember that else limits the run-time of your codes and put it on a more specified path for you.
{
//Here we will set up our method of data entry and decimal format
Scanner keyboard = new Scanner(System.in);
DecimalFormat eNotation1 = new DecimalFormat("00.00");
//Let's introduce our program to the user
System.out.println("Hi, This is a program to calculate quarterly interest growth");
//Here we will prompt the user to enter the amount of quarters
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
int quarterNumber = keyboard.nextInt();
//Here you had started your condition I'll try to make it nested if statement
if (quarterNumber > 10 || quarterNumber < 0)
//if the condition is true perform this
{
System.out.println("You entered a number outside of the boundrys. Please run the program again and choose a number between 0 and 10 (number can include 10)");
System.exit(0);
}
else{
//if false conditions inside else statement should be performed
//Here we will prompt the user for the starting balance.
System.out.println("What is the starting balance of this account?");
double startingBalance = keyboard.nextDouble();
//Here we will prompt the user for the interest rate
System.out.println("What is the interest rate (in percent) in your area? Please pick a number from 1 - 20.");
double interestRate = keyboard.nextDouble();
//you could put another if statement inside if statement which is known as nested if statement.
if (interestRate < 1 || interestRate > 20)
{
System.out.println("You entered a number outside of the boundrys. Please run the program again and choose a number between 1 and 20 (can include 1 and 20)");
System.exit(0);
}
else{
//like before you should enclose this to else to avoid confusion
//Here we will double check with the user that the info is correct.
System.out.println("The amount of quarters you would like displayed is " + quarterNumber);
System.out.println("The starting balance you would like to work with is " + startingBalance);
System.out.println("The interest rate in your area is " + interestRate);
System.out.println("Is this information correct?");
keyboard.nextLine();
String answer = keyboard.nextLine();
System.out.println("");
//We will have them enter the information again if the answer is no or No
if (answer == "no" || answer == "No")
{
//Here we will prompt the user to enter the amount of quarters
System.out.println("How many quarters would you like to display? Please pick a number greater than zero and less than or equal to 10");
keyboard.nextInt();
quarterNumber = keyboard.nextInt();
//Here we will prompt the user for the starting balance.
System.out.println("What is the starting balance of this account?");
keyboard.nextDouble();
startingBalance = keyboard.nextDouble();
//Here we will prompt the user for the interest rate
System.out.println("What is the interest rate (in percent) in your area? Please pick a number from 1 - 20.");
keyboard.nextDouble();
interestRate = keyboard.nextDouble();
}
//Next we will proceed with the calculation if the information is indeed correct
double endingBalance = startingBalance + (startingBalance * (interestRate / 100 * .25));
double interestEarned = endingBalance - startingBalance;
//Now we will output the information
for (int qn = 1; qn < (quarterNumber + 1); qn++ , startingBalance = startingBalance + interestEarned , endingBalance =startingBalance + (startingBalance * (interestRate / 100 * .25)), interestEarned = endingBalance - startingBalance )
{
System.out.println("Quarter Number Starting Balance Interest Earned Ending Balance ");
System.out.println(qn + " " + eNotation1.format(startingBalance) + " " + eNotation1.format(interestEarned) + " " + eNotation1.format(endingBalance) + " ");
}
}
}
}
Remember that learning nested if statement is essential to a programmer. without this, all your conditions will literally proceed.
// In the following program, initally when the user is greeted with the instructions he can simply enter the sentinel to exit the while loop, however, when you get the result of tickets you wish to buy, pressing 999 does not exit the program
import java.io.*;
public class ManyTickets
{
public static void main (String [] args) throws IOException
{
String userInput;
String userInput2;
int intInput = 0;
int intInput2 = 0;
double total = 0.00;
BufferedReader ageInput = new BufferedReader (new InputStreamReader (System.in));
try{
System.out.println("Please enter your age, or press '999' to exit.");
userInput = ageInput.readLine();
intInput = Integer.parseInt (userInput);
while (intInput != 999)
{
if (intInput < 0 || intInput > 110)
System.out.println("Invalid entry, or your age seems a bit too high to enter buy these tickets");
else if (intInput <= 12)
{
total = total + 6;
System.out.println("The ticket cost for 1 ticket is " + total);
}
else if (intInput <= 64)
{
total = total + 11;
System.out.println("The ticket cost for 1 ticket is " + total);
}
else
{
total = total + 8;
System.out.println("The ticket cost for 1 ticket is $" + total);
}
System.out.println("So far, your tickets cost is: $" + total );
System.out.print("Would you like to buy more tickets? You can buy up to 1 more ticket per customer! If no press 999 to exit");
userInput = ageInput.readLine();
intInput2 = Integer.parseInt (userInput);
}
}catch (NumberFormatException e){
System.out.println("Please restart the program, and enter an integer instead!");
}
}
{
double total = 0.0;
System.out.println("Thank you, The total cost for the ticket is: $" + total);
System.out.println("Have a nice day!");
}
}
You're using two different variables, intInput and intInput2. I don't see why you need the second one (right before the catch block). Just reuse intInput, which is the one being checked against the sentinel value in your while loop.
You are not doing anything after the user enters 999. Break the loop when its 999 as below,
intInput2 = Integer.parseInt(userInput);
if (intInput2 == 999) {
break;
}