When I try to compile this code, I keep coming up with compiling errors. The code is below.
import java.util.Scanner;
public class BaseballPitcher
{
private final int MAX_GAMES = 15;
private gamesPitched[];
private int totalGames;
private int totalRuns;
private float totalInnings;
private double ERA;
public BaseballPitcher()
{
gamesPitched = new GamePitched[];
}
public void inputGameData()
{
Scanner input = new Scanner (System.in);
do
{
System.out.printf ("How many games will you enter (up to %d): ", MAX_GAMES);
totalGames = input.nextInt();
if (totalGames <= 0 || totalGames > MAX_GAMES)
{
System.out.printf ("Error: You may only enter up to %d games" + " - Please try again\n\n", MAX_GAMES);
}
} while (totalGames <= 0 || totalGames > MAX_GAMES);
for (int x = 0, x < totalGames, x++)
{
gamesPitched[x] = new GamePitched();
gamesPitched[x].inputGame();
}
}
}
The compile errors I am receiving are:
[Please list your compile error or errors].
Why am I getting the compile errors?
It appears you have a custom class named GamePitched. Your array gamesPitched[] is likely supposed to be an array of this type, yet you have declared it without a type. Try private GamePitched[] gamesPitched;
Your loop just has syntax errors -- the , should be ;, which Java uses to separate the clauses in a for loop.
You should read the errors provided in the stacktrace. Even if you are new to Java, they are fairly descriptive and would help you identify where the problems exist (and often suggest the fix).
Well, this is how it should like, I guess
import java.util.Scanner;
public class BaseballPitcher
{
private final int MAX_GAMES = 15;
private GamePitched[] gamesPitched;
private int totalGames;
private int totalRuns;
private float totalInnings;
private double ERA;
public BaseballPitcher()
{
gamesPitched = new GamePitched[10];
}
public void inputGameData()
{
Scanner input = new Scanner (System.in);
do
{
System.out.printf ("How many games will you enter (up to %d): ", MAX_GAMES);
totalGames = input.nextInt();
if (totalGames <= 0 || totalGames > MAX_GAMES)
{
System.out.printf ("Error: You may only enter up to %d games" + " - Please try again\n\n", MAX_GAMES);
}
} while (totalGames <= 0 || totalGames > MAX_GAMES);
for (int x = 0; x < totalGames; x++)
{
gamesPitched[x] = new GamePitched();
gamesPitched[x].inputGame();
}
}
}
at least to compile. Cannot say anything about the logic
and the other class must have at least this method
public class GamePitched {
public void inputGame() {
// TODO Auto-generated method stub
}
}
Related
I'm trying to create a program that asks for 10 integers and puts those numbers into an array of negative, positive, and odd arrays. In the end, I want the program to print out 3 rows of numbers that separate the users 10 numbers into "odd", "even", and negative". When I run this I get "error: 'void' type not allowed here"
import java.util.Scanner;
public class ArrayPractice{
private static void showArray(int[] nums)
{
for (int i=0; i<nums.length;i++)
{
if(nums[i]!=0)
{
System.out.println(nums[i] + " ");
}
}
}
public static void main(String[] args){
int evenArray[] = new int[10];
int evenCount = 0;
int oddArray[] = new int[10];
int oddCount = 0;
int negArray[] = new int[10];
int negCount = 0;
Scanner input = new Scanner(System.in);
for(int i = 0; i<10; i++)
{
System.out.println("Number? " + (i + 1));
int answer = input.nextInt();
if(answer<0)
{
negArray[negCount++] = answer;
}
else
{
if (answer % 2 == 0)
{
evenArray[evenCount++] = answer;
}
else
{
oddArray[oddCount++] = answer;
}
}
}
System.out.println(showArray(evenArray));
System.out.println(showArray(oddArray));
System.out.println(showArray(negArray));
}
}
showArray is void, it does not return anything. And, on inspection, it prints in the method itself. So this
System.out.println(showArray(evenArray));
System.out.println(showArray(oddArray));
System.out.println(showArray(negArray));
should just be
showArray(evenArray);
showArray(oddArray);
showArray(negArray);
I am new to Java and I needed dynamic Array ... all of thing I found that's for dynamic Array we should use "Array List' that's ok but when I want the indexes to be the power of X that given from input , I face ERORR ! .. the indexes are unclear and the are not specified what is the first or 2th power ! .... can anyone help me how solve it?
public static void main(String[] args) throws Exception {
Scanner Reader = new Scanner(System.in);
ArrayList<Float> Zarayeb = new ArrayList<Float>();
Float s ;
int m;
System.out.print("Add Count of equation Sentences : ");
int N = Reader.nextInt();
if (N == 0)
return;
for (int i = 0; i < N ; i++) {
s = Reader.nextFloat() ;
System.out.print("x^");
m = Reader.nextInt();
if (Zarayeb.get(m)== null)
Zarayeb.add(0 , s);
else{
Float l ;
l = Zarayeb.get(m);
Zarayeb.add (m , l+s);
}
if (i < N-1)
System.out.print("\r+");
}
System.out.print("Add Count of equation Sentences : ");
N = Reader.nextInt();
if (N == 0)
return;
for (int i = 0; i < N ; i++) {
s = Reader.nextFloat() ;
System.out.print("x^");
m = Reader.nextInt();
if (Zarayeb.get(m)== null)
Zarayeb.add(m , s);
else{
Float l ;
l = Zarayeb.get(m);
Zarayeb.add (m , l+s);
}
if (i < N-1)
System.out.print("\r+");
}
System.out.print("Enter X: ");
float X = Reader.nextFloat();
float Sum = 0;
for (int i = 0; i < Zarayeb.size();i++) {
Sum += (Zarayeb.get(i) * Math.pow(X,i));
}
System.out.println("\nThe final answer is : " + Sum);
First I refactored your code a bit to make sense of it:
Main class with the top level logic:
import java.util.Scanner;
public class Main {
private Scanner scanner;
private final Totals totals = new Totals();
public static void main(final String[] args) {
final Main app = new Main();
app.run();
}
private void run() {
scanner = new Scanner(System.in);
try {
readAndProcessEquationSentences();
} finally {
scanner.close();
}
}
private void readAndProcessEquationSentences() {
readSentences(true);
readSentences(false);
System.out.println("The final answer is : " + totals.calculateSum(readBaseInput()));
}
private void readSentences(final boolean useInitialLogic) {
System.out.print("Enter number of equation sentences:");
final int numberOfSentences = scanner.nextInt();
if (numberOfSentences == 0) {
throw new RuntimeException("No sentences");
}
for (int i = 0; i < numberOfSentences; i++) {
Sentence sentence = Sentence.read(scanner);
if (useInitialLogic) {
totals.addInitialSentence(sentence);
} else {
totals.addNextSentence(sentence);
}
if (i < numberOfSentences - 1) {
System.out.print("\r+");
}
}
}
private float readBaseInput() {
System.out.print("Enter base: ");
return scanner.nextFloat();
}
}
Sentence class which represents one equation sentence entered by the user:
import java.util.Scanner;
public class Sentence {
private Float x;
private int y;
public static Sentence read(final Scanner scanner) {
final Sentence sentence = new Sentence();
System.out.println("Enter x^y");
System.out.print("x=");
sentence.x = scanner.nextFloat();
System.out.println();
System.out.print("y=");
sentence.y = scanner.nextInt();
System.out.println();
return sentence;
}
public Float getX() {
return x;
}
public int getY() {
return y;
}
}
Totals class which keeps track of the totals:
import java.util.ArrayList;
import java.util.List;
public class Totals {
private final List<Float> values = new ArrayList<Float>();
public void addInitialSentence(final Sentence sentence) {
if (values.size() <= sentence.getY()) {
addToStart(sentence);
} else {
addToValue(sentence);
}
}
private void addToStart(final Sentence sentence) {
values.add(0, sentence.getX());
}
public void addNextSentence(final Sentence sentence) {
if (values.size() <= sentence.getY()) {
values.add(sentence.getY(), sentence.getX());
} else {
addToValue(sentence);
}
}
private void addToValue(final Sentence sentence) {
Float total = values.get(sentence.getY());
total = total + sentence.getX();
values.add(sentence.getY(), total);
}
public float calculateSum(final float base) {
float sum = 0;
for (int i = 0; i < values.size(); i++) {
sum += (values.get(i) * Math.pow(base, i));
}
return sum;
}
}
I don't have the foggiest idea what this is supposed to do. I named the variables according to this foggy idea.
You are letting the user input values in two separate loops, with a slightly different logic I called 'initial' and 'next'.
In the initial loop you were doing this:
if (Zarayeb.get(m) == null)
Zarayeb.add(0 , s);
In the next loop this:
if (Zarayeb.get(m) == null)
Zarayeb.add(m , s);
There are problems with this because the ArrayList.get(m) will throw an IndexOutOfBoundException if m is out or range. So I changed that to the equivalent of:
if (Zarayeb.size() <= m) {
....
}
However, in the 'next' case this still does not solve it. What should happen in the second loop when an 'm' value is entered for which no element yet exists in the ArrayList?
Why do you need to enter sentences in two loops?
What is the logic supposed to achieve exactly?
Exception in thread "main" java.lang.NullPointerException
at Game.main(Game.java:12)
Ive tried searching and this apparently means that im trying to assign a value to a null during
" machines[0].setPayoutRate(35); "
When I try and debug the program the array of objects doesn't show up as three objects. Just one with the value of " SlotMachine[3] " which doesn't make much sense to me. Any ideas?
import java.util.Scanner;
public class Game {
public static void main(String[] args) {
Scanner userInput = new Scanner(System.in);
SlotMachine[] machines;
machines = new SlotMachine[3];
int cash = 0, totalPlays = 0;
machines[0].setPayoutRate(35);
machines[1].setPayoutRate(100);
machines[2].setPayoutRate(10);
machines[0].setPayoutAmount(30);
machines[1].setPayoutAmount(60);
machines[2].setPayoutAmount(11);
System.out.println("How many quarters do you have?");
cash = userInput.nextInt();
System.out.println("how many times has the first machine been played?");
machines[0].settimesPlayed(userInput.nextInt());
System.out
.println("how many times has the second machine been played?");
machines[1].settimesPlayed(userInput.nextInt());
System.out.println("how many times has the third machine been played?");
machines[2].settimesPlayed(userInput.nextInt());
while (cash >= 1) {
if (cash >= 1) {
cash = machines[0].play();
totalPlays++;
}
if (cash >= 1) {
cash = machines[0].play();
totalPlays++;
}
if (cash >= 1) {
cash = machines[0].play();
totalPlays++;
}
}
System.out.println("You played: " + totalPlays + " times.");
}
}
Main class is above^
Object class is below
public class SlotMachine {
private int timesPlayed;
private int payoutRate;
private int payoutAmount;
public SlotMachine(int timesPlayed, int payoutRate, int payoutAmount) {
this.timesPlayed = timesPlayed;
this.payoutRate = payoutRate;
this.payoutAmount = payoutAmount;
}
public int getTimesPlayed() {
return this.timesPlayed;
}
public void settimesPlayed(int timesPlayed) {
this.timesPlayed = timesPlayed;
}
public int getPayoutRate() {
return this.payoutRate;
}
public void setPayoutRate(int payoutRate) {
this.payoutRate = payoutRate;
}
public int getPayoutAmount() {
return this.payoutAmount;
}
public void setPayoutAmount(int payoutAmount) {
this.payoutAmount = payoutAmount;
}
public int play() {
int moneyExchange = 0;
timesPlayed++;
if (timesPlayed != payoutRate) {
moneyExchange = -1;
} else if (timesPlayed == payoutRate) {
moneyExchange = payoutAmount;
timesPlayed = 0;
}
return moneyExchange;
}
}
You declared your array of length 3, but it's not assigned any new SlotMachines, so all elements remain null, causing the NullPointerException. Initialize your array elements.
machines = new SlotMachine[3];
machines[0] = new SlotMachine(0, 35, 30);
machines[1] = new SlotMachine(0, 100, 60);
machines[2] = new SlotMachine(0, 10, 11);
Then you can access them through the array.
When you declare your array with a size of 3, the array is created with null for each slot.
Then, you try to call a method on null. This will return a Null Pointer Exception.
You need to add objects (in this case SlotMachine) in the array that can have setPayoutRate() called on them.
For example, you can declare your array as follow:
Assign SlotMachine objects to machines reference
machines = new SlotMachine[3];
for (int i = 0; i < machines.length; i++) {
int timesPlayed=000;
int payoutRate=000;
int payoutAmount=000;
machines[i] = new SlotMachine(timesPlayed,payoutRate,payoutAmount);
}
It's because your creating an instance of the array, but not of the objects it contains.
SlotMachine[] machines;
machines = new SlotMachine[3];
You need to add:
for (int i=0; i<3; i++) {
machines[i] = new SlotMachine();
}
So im trying to do cross-sums: 321=6 because 3+2+1=6 however ive run into a problem that i can locate with my code and was hoping if anyone else could help me to locate it
import java.util.*;
public class Thewierdo {
public static void main(String[] args) {
Scanner Tinput = new Scanner (System.in);
System.out.print("input number for cross-sum examination: ");
Double Tin = Tinput.nextDouble();
int m = 0;
if (Tin.isNaN()){
System.out.print("actual whole number please: ");
Tin = Tinput.nextDouble();
}else{
int cool = Tin.intValue();
String gotcha= String.valueOf(cool);
int heads = gotcha.length();
while(heads >= 0){
System.out.println(gotcha.charAt(1));
char Tails=gotcha.charAt(heads);
int finald = Character.getNumericValue(Tails);
heads=heads-1;
m += finald;
//made by Christian Risom
}
System.out.print(m);
}
}
}
That's my solution, i'm sure you could make it more simple, but there you go:
public static int cross_sums(int input) {
int output = 0;
do {
output += input % 10;
input /= 10;
} while (input > 0);
if (output > 9) {
output = cross_sums(output);
}
return output;
}
The way you are checking if it is a valid number doesn't work. An error will be thrown on Tinput.nextDouble() if the input can't be interpreted as a double.
As others are saying, read your errors and debug. You likely have other problems as well.
I'm solving Uva's 3n+1 problem and I don't get why the judge is rejecting my answer. The time limit hasn't been exceeded and the all test cases I've tried have run correctly so far.
import java.io.*;
public class NewClass{
/**
* #param args the command line arguments
*/
public static void main(String[] args) throws IOException {
int maxCounter= 0;
int input;
int lowerBound;
int upperBound;
int counter;
int numberOfCycles;
int maxCycles= 0;
int lowerInt;
BufferedReader consoleInput = new BufferedReader(new InputStreamReader(System.in));
String line = consoleInput.readLine();
String [] splitted = line.split(" ");
lowerBound = Integer.parseInt(splitted[0]);
upperBound = Integer.parseInt(splitted[1]);
int [] recentlyused = new int[1000001];
if (lowerBound > upperBound )
{
int h = upperBound;
upperBound = lowerBound;
lowerBound = h;
}
lowerInt = lowerBound;
while (lowerBound <= upperBound)
{
counter = lowerBound;
numberOfCycles = 0;
if (recentlyused[counter] == 0)
{
while ( counter != 1 )
{
if (recentlyused[counter] != 0)
{
numberOfCycles = recentlyused[counter] + numberOfCycles;
counter = 1;
}
else
{
if (counter % 2 == 0)
{
counter = counter /2;
}
else
{
counter = 3*counter + 1;
}
numberOfCycles++;
}
}
}
else
{
numberOfCycles = recentlyused[counter] + numberOfCycles;
counter = 1;
}
recentlyused[lowerBound] = numberOfCycles;
if (numberOfCycles > maxCycles)
{
maxCycles = numberOfCycles;
}
lowerBound++;
}
System.out.println(lowerInt +" "+ upperBound+ " "+ (maxCycles+1));
}
}
Are you making sure to accept the entire input? It looks like your program terminates after reading only one line, and then processing one line. You need to be able to accept the entire sample input at once.
I faced the same problem. The following changes worked for me:
Changed the class name to Main.
Removed the public modifier from the class name.
The following code gave a compilation error:
public class Optimal_Parking_11364 {
public static void main(String[] args) {
...
}
}
Whereas after the changes, the following code was accepted:
class Main {
public static void main(String[] args) {
...
}
}
This was a very very simple program. Hopefully, the same trick will also work for more complex programs.
If I understand correctly you are using a memoizing approach. You create a table where you store full results for all the elements you have already calculated so that you do not need to re-calculate results that you already know (calculated before).
The approach itself is not wrong, but there are a couple of things you must take into account. First, the input consists of a list of pairs, you are only processing the first pair. Then, you must take care of your memoizing table limits. You are assuming that all numbers you will hit fall in the range [1...1000001), but that is not true. For the input number 999999 (first odd number below the upper limit) the first operation will turn it into 3*n+1, which is way beyond the upper limit of the memoization table.
Some other things you may want to consider are halving the memoization table and only memorize odd numbers, since you can implement the divide by two operation almost free with bit operations (and checking for even-ness is also just one bit operation).
Did you make sure that the output was in the same order specified in the input. I see where you are swapping the input if the first input was higher than the second, but you also need to make sure that you don't alter the order it appears in the input when you print the results out.
ex.
Input
10 1
Output
10 1 20
If possible Please use this Java specification : to read input lines
http://online-judge.uva.es/problemset/data/p100.java.html
I think the most important thing in UVA judge is 1) Get the output Exactly same , No Extra Lines at the end or anywhere . 2) I am assuming , Never throw exception just return or break with No output for Outside boundary parameters.
3)Output is case sensitive 4)Output Parameters should Maintain Space as shown in problem
One possible solution based on above patterns is here
https://gist.github.com/4676999
/*
Problem URL: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=36
Home>Online Judge > submission Specifications
Sample code to read input is from : http://online-judge.uva.es/problemset/data/p100.java.html
Runtime : 1.068
*/
import java.io.*;
import java.util.*;
class Main
{
static String ReadLn (int maxLg) // utility function to read from stdin
{
byte lin[] = new byte [maxLg];
int lg = 0, car = -1;
String line = "";
try
{
while (lg < maxLg)
{
car = System.in.read();
if ((car < 0) || (car == '\n')) break;
lin [lg++] += car;
}
}
catch (IOException e)
{
return (null);
}
if ((car < 0) && (lg == 0)) return (null); // eof
return (new String (lin, 0, lg));
}
public static void main (String args[]) // entry point from OS
{
Main myWork = new Main(); // create a dinamic instance
myWork.Begin(); // the true entry point
}
void Begin()
{
String input;
StringTokenizer idata;
int a, b,max;
while ((input = Main.ReadLn (255)) != null)
{
idata = new StringTokenizer (input);
a = Integer.parseInt (idata.nextToken());
b = Integer.parseInt (idata.nextToken());
if (a<b){
max=work(a,b);
}else{
max=work(b,a);
}
System.out.println (a + " " + b + " " +max);
}
}
int work( int a , int b){
int max=0;
for ( int i=a;i<=b;i++){
int temp=process(i);
if (temp>max) max=temp;
}
return max;
}
int process (long n){
int count=1;
while(n!=1){
count++;
if (n%2==1){
n=n*3+1;
}else{
n=n>>1;
}
}
return count;
}
}
Please consider that the integers i and j must appear in the output in the same order in which they appeared in the input, so for:
10 1
You should print
10 1 20
package pandarium.java.preparing2topcoder;/*
* Main.java
* java program model for www.programming-challenges.com
*/
import java.io.*;
import java.util.*;
class Main implements Runnable{
static String ReadLn(int maxLg){ // utility function to read from stdin,
// Provided by Programming-challenges, edit for style only
byte lin[] = new byte [maxLg];
int lg = 0, car = -1;
String line = "";
try
{
while (lg < maxLg)
{
car = System.in.read();
if ((car < 0) || (car == '\n')) break;
lin [lg++] += car;
}
}
catch (IOException e)
{
return (null);
}
if ((car < 0) && (lg == 0)) return (null); // eof
return (new String (lin, 0, lg));
}
public static void main(String args[]) // entry point from OS
{
Main myWork = new Main(); // Construct the bootloader
myWork.run(); // execute
}
public void run() {
new myStuff().run();
}
}
class myStuff implements Runnable{
private String input;
private StringTokenizer idata;
private List<Integer> maxes;
public void run(){
String input;
StringTokenizer idata;
int a, b,max=Integer.MIN_VALUE;
while ((input = Main.ReadLn (255)) != null)
{
max=Integer.MIN_VALUE;
maxes=new ArrayList<Integer>();
idata = new StringTokenizer (input);
a = Integer.parseInt (idata.nextToken());
b = Integer.parseInt (idata.nextToken());
System.out.println(a + " " + b + " "+max);
}
}
private static int getCyclesCount(long counter){
int cyclesCount=0;
while (counter!=1)
{
if(counter%2==0)
counter=counter>>1;
else
counter=counter*3+1;
cyclesCount++;
}
cyclesCount++;
return cyclesCount;
}
// You can insert more classes here if you want.
}
This solution gets accepted within 0.5s. I had to remove the package modifier.
import java.util.*;
public class Main {
static Map<Integer, Integer> map = new HashMap<>();
private static int f(int N) {
if (N == 1) {
return 1;
}
if (map.containsKey(N)) {
return map.get(N);
}
if (N % 2 == 0) {
N >>= 1;
map.put(N, f(N));
return 1 + map.get(N);
} else {
N = 3*N + 1;
map.put(N, f(N) );
return 1 + map.get(N);
}
}
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
try {
while(scanner.hasNextLine()) {
int i = scanner.nextInt();
int j = scanner.nextInt();
int maxx = 0;
if (i <= j) {
for(int m = i; m <= j; m++) {
maxx = Math.max(Main.f(m), maxx);
}
} else {
for(int m = j; m <= i; m++) {
maxx = Math.max(Main.f(m), maxx);
}
}
System.out.println(i + " " + j + " " + maxx);
}
System.exit(0);
} catch (Exception e) {
}
}
}