Develop Reference

Variable value not correctly increasing

In my code I have a variable, points, that increments based on the consanants and vowels in strings inputted. The method parseSentence is supposed to increase points per word but also ignore spaces.
I've tried running a debugger to see where the problem is but the debugger dies when it reaches the for loop in parseSentence. The method makes the point variable's value the word's point value instead of adding it to the variable. What could be causing this?
import java.util.*;
public class WordGolf1 {
public static int points = 1;
public static void main(String[] args) {
String Input;
System.out.println("Enter word: ");
Scanner sc = new Scanner(System.in);
Input = sc.nextLine();
System.out.println("Not enough points. " + (100 - points) + " needed.");
while (points < 100) {
System.out.println("Enter word: ");
Input = sc.nextLine();
parseSentence(Input);
System.out.println(points + ": points");
System.out.println("Not enough points. " + (100 - points) + " needed.");
}
boolean overshot = true;
Loop:
while (overshot = true) {
if (points == 100) {
overshot = false;
break Loop;
}
points = 100 - (points - 100);
System.out.println("Overshot by " + (points - 100) + " points.");
Input = sc.nextLine();
parseSentence(Input);
}
System.out.println("Congratulations you win!");
sc.close();
}
public static int parseSentence(String input) {
String[] pieces = input.split("\\s+");
for (int y = 0; y < pieces.length; y++) {
if (pieces.length > 1) {
if (y == 0) {
parseWord(input);
} else {
parseWord(input, y);
}
} else {
parseWord(input);
}
}
return points;
}
public static int parseWord(String input) {
String[] pieces = input.split("\\s+");
String charList = "aeiouyAEIOUY";
String consanantList
= "bcdfghjklmnpqrstvwxzBCDFGHJKLMNPQRSTVWXZ";
int pointsTemp = 1;
for (int x = 0; x < pieces[0].length(); x++) {
if (charList.indexOf(pieces[0].charAt(x)) != -1) {
pointsTemp *= 2;
} else if (consanantList.indexOf(pieces[0].charAt(x))
!= -1) {
pointsTemp++;
}
}
points = pointsTemp;
return points;
}
public static int parseWord(String input, int number) {
String[] pieces = input.split("\\s+");
String charList = "aeiouyAEIOUY";
String consanantList
= "bcdfghjklmnpqrstvwxzBCDFGHJKLMNPQRSTVWXZ";
int pointsTemp = 1;
for (int x = 0; x < pieces[number].length(); x++) {
if (charList.indexOf(pieces[number].charAt(x)) != -1) {
pointsTemp *= 2;
} else if (consanantList.indexOf(pieces[number].charAt(x)) != -1) {
pointsTemp++;
}
}
points += pointsTemp;
return points;
}
}

You are not using the value returned by the parseSentence method.

Edit: I tried to rewrite this to be as close your original code with making the changes I feel where necessary.
Now Obviously your teacher has requirements and we can't go against that, but some points of interest you should keep in mind.
Multi Splitting
In your example you split the text to get the amount of words. Then instead of looping the already split text. You are sending the original input and then splitting it again. The "Double" splitting is why you needed "three" methods. If you don't double split you can simply loop the length from the single split and just use a single ParseWord method.
Deducting Values
In your example you take away 100 if the player overshot. The problem with this is let's say the person received a score like 200. Then it would loop twice to lower the value submitting the "You overshot message" twice. However let's say by some magical way a score of 100,000,000 was received. Then as you can see we would loop 1 million times to deduct this value essentially creating an not infinite but might as well be infinite loop.
To resolve this problem we simply do the below.
Value = Value % 100.
This will give us the remainder of our Value between 0 and 99. I.e. 167 will equal 67 and 12384 will be equal 84.
Using String (IndexOf)
What this does is takes the Character you provided and loop iterates over the String you provided. The worst case is 12 loops. There's also a lot of other stuff String and IndexOf do that is extra work and I recommend staying away from it if you can.
The alternative solution which I did is take the character and use " | 32" on it. I'm not going to go deep into how bits work, but basically these characters are 8 bit values but we only use 7 of it's bits ranging from 32 to 127. The amount of bits is like the power of 2. so 2^7 = 128 and 2^8 = 256. When we perform the "|" we are turning a bit on so if it's already on it won't change the value.
So in our example let's say we have the value 64.
This is bit 6 turned on. Now we want to turn on bit 5 "32" so the value becomes 96, but if we already had the value 96 and we turn bit 32 on it will still be 32.
Full List of ASCII Characters..
https://www.ascii-code.com/
The Game Loop
In your example you created "TWO" game loops the first one is when you start off, but once you overshot your score you enter the second loop and forget the first one. The problem is now your "Enter Words" and "You Undershot" code are never used anymore. So all someone will see is the line to enter text with no information on what to do or what occurred unless they overshot then they get the overshot message.
To fix this I made a single Game Loop which processes until the code ends via the SCORE == 100. You can see in the code that we begin every game loop with "Enter Words: " and parse the sentence. Then we add up our score and compare. If we undershot we simply restart the loop and try again. If we overshot we reduce the score and try again. If we succeeded we prompt the user if they would like to play again or end the game. Playing again will set the SCORE to 0 and start over the loop. Ending the game will "BREAK" the loop and cause it to end.
The Full Working Code With Recommended Changes
Feel free to comment if you need additional assistance.
import java.util.*;
public class WordGolf1
{
private static int SCORE = 0;
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
while (true)
{
System.out.print("\n\nEnter word: ");
ParseSentence(sc.nextLine());
if (SCORE == 100)
{
System.out.print("\nYou Won! Would you like to play again: Y/N?");
if ((sc.nextLine().charAt(0) | 32) == 'y')
{
SCORE = 0;
System.out.print("\nResetting Game...");
} else {
break;
}
}
else
{
if (SCORE > 100)
{
int overshot = SCORE - 100;
SCORE = SCORE % 100;
System.out.print("\nYou Overshot By " + overshot + " Points. You now have " + SCORE + " points.");
} else {
System.out.print("\nYou currently have " + SCORE + " points you need " + (100 - SCORE) + " more.");
}
}
}
}
private static int ParseSentence(String input)
{
String[] split = input.split(" ");
for (Strng s : input)
SCORE += ParseWord(s);
}
private static int ParseWord(String word)
{
int value = 1;
for (int i = 0; i < word.length(); ++i)
{
int c = (int)word.charAt(i) | 32;
if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u')
{
value *= 2;
} else {
value += 1;
}
}
return value;
}
}

Setting up a highscore by using arrays

So our teacher told us to create a JApplet with a highscore.
He wanted us to use an Arraylist which contains 10 integer values. If u press a JButton these values are getting displayed in a JLabel. And you can enter a number and where it is placed in the Array. Like if I enter 10 and in the other text field 0, the number 10 is the first number which gets displayed when I press the button. But the other 10 integer values are supposed to move one digit up in the array.
e.g I enter nothing I get displayed
1,2,3,4,5,6,7,8,9,10
and when I enter 10 and 0 it should display
10,1,2,3,4,5,6,7,8,9,10.
My problem is that I don't get how to move the numbers like I can only get this thing if I enter 10 and 0:
10,2,3,4,5,6,7,8,9,10
Here is my Code:
public void neueListe (int Stelle,int Zahl, int[] highscore){
highscore[Stelle] = Zahl;
}
public void jButton1_ActionPerformed(ActionEvent evt) {
int Stelle = Integer.parseInt(jTextField2.getText());
int Zahl = Integer.parseInt(jTextField1.getText());
int[] highscore = new int [10];
highscore[0]=1;
highscore[1]=2;
highscore[2]=3;
highscore[3]=4;
highscore[4]=5;
highscore[5]=6;
highscore[6]=7;
highscore[7]=8;
highscore[8]=9;
highscore[9]=10;
neueListe(Stelle,Zahl, highscore);
jLabel1.setText(""+ highscore[0]+", " + highscore[1]+", " + highscore[2]+", "+ highscore[3] + highscore[4] + highscore[5] + highscore[6] + highscore[7] + highscore[8] + highscore[9]);
}

Convert your int[] into ArrayList and then simply add any element at any position using add method.
ArrayList<Integer> arr = new ArrayList<>(Arrays.asList(highscore));
arr.add(Zahl, Stelle); // arr.add(position, value)
System.out.println(arr);
if you want to print all no.s as string then use this.
String labelshow = "";
for(Integer item: arr){
labelshow += "," + item;
}
jLabel1.setText(labelshow);
Or you can simply put your no. in required position and shift rest of the elements towards right using a for loop.(size would be increased keep this in mind.)
int newarray[] = new int[highscore.length+1];
for(int i=0, j=0; i<highscore.length+1; i++){
if(i == Zahl){
newarray[i] = Stelle;
}
else{
newarray[i] = highscore[j++];
}
}
newarray contains your resultant array. You can print it or show it in JLabel.

why do my simple arrays not work?

This program should ask how many of an animal are left in the wild 5 times. Then it should use a second method to output the same information. But i cant figure this out; every time i change anything based on previous questions here i just add to the number of errors.
import java.util.Scanner;
class animals {
public static void main(String[] args) {
int[] q1 = question();
output(q1);
System.exit(0);
} // exit main
public static int[] question() {
String[] wild = { "Komodo Dragon", "Mantee", "Kakapo", "Florida Panther", "White Rhino" };
int number = 0;
int[] record = {};
for (int i = 1; i <= 5; i++) {
System.out.println(wild[number] + ":");
Scanner scanner = new Scanner(System.in);
System.out.println("How many are left in the wild?");
int howMany = scanner.nextInt();
record = new int[] {howMany};
number++;
}//end for loop
return record;
}// end method question
public static void output(int[] q1){
System.out.println("There are " + q1[0] + " Komodo Dragons in the wild");
System.out.println("There are " + q1[1] + " Mantees in the wild");
System.out.println("There are " + q1[2] + " Kakapos in the wild");
System.out.println("There are " + q1[3] + " Florida Panthers in the wild");
System.out.println("There are " + q1[4] + " White Rhinos in the wild");
}//end method output
} // end class animals
So this compiles alright, then when i've added 5 numbers in terminal after each loop i get
There are 3 Komodo Dragons in the wild
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
at animals.output(animals.java:39)
at animals.main(animals.java:13)
Other than the fact that im getting the text, the monodo dragon number being provided is the last number i input not the first

This doesn't make sense
int[number] record = {};
most like what you meant was
int[] record = new int[wild.length];
and instead of
for (int i = 1; i <= 5; i++) {
you need
for (int i = 0; i < wild.length; i++) {
instead of the following which creates an array of 1 value [0]
record = new int[] {howMany};
which will produce the following when you try to access [1]
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
you need
record[i] = howMany;
As you write each line of code in your IDE (or your editor) you should see if that compiles and if it doesn't adding more lines is unlikely to help. I suggest you try to compile and test as often as possible so you know where the source of your errors are and when you get a bug, you can step through the code in your debugger to see why the program is not doing what you expect.

This is what you need:
int number = 0;
int[] record = new int[5];
and another modification which you need to make:
int howMany = scanner.nextInt();
record[number] = howMany;
Remove comment from last line.
Now your program should work fine.
Learn some basic stuff about arrays.

Get the next sequence in an arithmetic or geometric progression

I want to make an application that takes a sequence of 3 numbers per line to produce and stops when it reaches a sequence of zeros and then prints if it's an arithmetic progression or geometric progression and the next number in the series.
Example input:
4 7 10
2 6 18
0 0 0
should output
AP 13
GP 54
here is my code I wanna know what's wrong with it and what are the possibilities that won't work with my code.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main
{
static String s="";
public static void main (String[] args) throws IOException
{
String c;
String a[];
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
do {
c= br.readLine();
a = c.split(" ");
if(c.charAt(0)!='0'){
calc(a[1], a[2]);
}
}while((c.charAt(0))!='0');
printer(s);
}
public static void calc(String a, String b){
int x = Integer.parseInt(a);
int y = Integer.parseInt(b);
if(y%x==0){
s += "GP" +" " + (y*(y/x)) + "z";
return;
}else{
s += "AP" + " " + (y + (y-x)) + "z";
return;
}
}
public static void printer(String s){
String p= "";
for(int i =0;i<=s.length()-1;i++){
if(s.charAt(i)!='z'){
p+= s.charAt(i);
}else{
System.out.println(p);
p= "";
}
}
}
}

Your problem it that you discover progression type incorrectly. For example, 0 4 8 is obviously AP, but your algorithm will say it is GP. Another example: 8 4 2 is GP, but 2%4 will return false, saying it is AP. Also, you don't proceed cases when offered sequence is not progression at all.
It is absolutely clear that all 3 numbers should be involved. Suppose that integer numbers a, b, c form AP or GP, and you need to discover which progression it is. Simple math can be used:
If they form AP, then a + c = b + b. Next element is c + c - b
If they form GP, then a * c = b * b. Next element is c * c / b
(Please notice how + is changed to *, and - to /, when you switch from AP to GP).

Your code works on the assumption that if two consecutive numbers of a 3 number series is divisible, the series is a GP and that if it's not, it has to be an AP. This assumption is wrong. There are many cases in which it will not be true, such as a series 0,3,6. It is an AP, not a GP. So instead of sending 2 parameters to the function calc(), you should send all three numbers as parameters, and check as follows:
if((a+c)==(2*b))
{//AP
}
else if((a*c)==(b*b))
{//GP
}
These above are the proper check for Arithmetic and Geometric progressions. Also while checking if the inputs are all 0, you are only checking for the first element. Instead you have to see if all three of the elements are 0. Your code might not work in the case of 0,3,6 or 0,2,4 or 0,1,2. So instead you have to check like this:
int flag=0;
for(int i=0;i<3;i++)
if(Integer.parseInt(a[i]))
flag=1;
if(flag==1)
{//continue prog
}
else
{//Terminate prog as input is 0,0,0
}

Number guessing game keeps repeating same questions and guesses incorrectly

If you run the the game you can see that certain numbers the game cannot guess correctly. For example if your number is 13 the game will loop two times too many and will also guess your number as 12 instead of 13. I think this is an issue with the counting but I've tried tracing the loops repeatedly but cannot find the error. I think the issue mainly lies within my while loop.
//import statements
import java.util.Scanner;
public class Numbers
{
public static void binarySearch()
{
int position=0;
String answer;
int upper_BOUND=100;
int lower_BOUND=0;
Scanner input=new Scanner(System.in);
while( (lower_BOUND <= upper_BOUND))
{
position = (lower_BOUND + upper_BOUND) / 2;
System.out.println("Is your value greater than " + position + "?");
answer=input.next();
if((upper_BOUND-lower_BOUND<=1))
{
break;
}
if (answer.equals("no")) // If the number is > key, ..
{ // decrease position by one.
upper_BOUND = position --;
}
if(answer.equals("yes"))
{
lower_BOUND = position ++; // Else, increase position by one.
}
}
System.out.println("Is your number " + position + "?");
String answer2=input.next();
System.out.println(position+" is the answer.\n Thank you for playing the guessing game.");
//else
// System.out.println("Bruh pick a number from 1 to 100 ");
}
}
......
tester class
public class NumberGuesser
{
public static void main(String[] args)
{
int[ ] num = new int [100];
// Fill array
for (int i = 0; i <= 99; i++)
num[i]=i;
//The search method
Numbers.binarySearch();
}
}

Your issue should be with the increment that you do in "lower_BOUND = position ++; " here what happens is when you increment the position value, the "++" first increments and then assigns the value to position variable. The lowerbound is not actually assigned the incremented value of position but old value of positon. So please make a change to "lower_BOUND = ++ position ; "
Like below
if(answer.equals("yes"))
{
lower_BOUND = ++ position ; // Else, increase position by one.
}
And also my suggestion is to check your " if((upper_BOUND-lower_BOUND <= 1))" condition. I guess the condition should be like this " if((upper_BOUND-lower_BOUND == 0)) "
And please remove unused code in your "NumberGuesser" class, this will confuse people who are trying to answer your question.