I am trying to make some kind of 'Evil Hangman game' (nifty Stanford CS exercises). The purpose of the game is to 'cheat' by removing as many possible word solutions as possible so the user cannot guess before the very end.
I have made a loop (below) which seems to remove many of the words possible words but for some reason it does not remove all of them. The input is a dictionary.txt file which contains about 120K words.
When I 'guess' the letter "a" it will take away roughly 60-70% of the words with "a" in them (estimate based on comparisons between the output with the first couple of words in the txt file)
File file = new File("dictionary.txt");
Scanner textScan = new Scanner(file);
List<String> wordList = new ArrayList<String>();
while ( textScan.hasNext() )
{
word = textScan.next();
wordList.add(word);
}
System.out.println("The ArrayList has " + wordList.size() + " objects stored in it.");
Scanner textScan1 = new Scanner(file);
for(int i = 0; i <= guessNumber; i++)
{
Collections.sort(wordList);
System.out.println("Type in your guess as a letter ");
String guess = keyboard.next();
guess = guess.toLowerCase();
while ( textScan1.hasNext() )
{
String word1 = textScan1.next();
if (wordLength != word1.length() && word1.contains(guess))
{
wordList.remove(word1);
}
}
}
I am aware that my code is a bit messy at this point, I am trying to improve everything about my programming so all feedback is greatly appreciated! I have the feeling that I am including stuff that does not have to be there and so on.
I will post the whole code below in case that helps:
import java.util.*;
import java.lang.*;
import java.io.*;
public class EvilHangman
{
public static void main(String[] args) throws IOException
{
// declaring variables
int wordLength;
int guessNumber;
// initiate the scanner
Scanner keyboard = new Scanner( System.in );
// introduction and prompting the user for word length
System.out.println("Welcome to Hangman. Let's play! ");
System.out.println("Please enter the desired word length: ");
wordLength = keyboard.nextInt();
while(wordLength < 0 || wordLength > 26)
{
System.out.println("This is not a valid word length. ");
System.out.println("Please enter the desired word length: ");
wordLength = keyboard.nextInt();
}
// prompt the user for number of guesses
System.out.println("How many guesses do you want to have? ");
guessNumber = keyboard.nextInt();
while(guessNumber < 0)
{
System.out.println("Number of guesses has to be a postive integer. ");
System.out.println("Please enter the desired number of guesses: ");
guessNumber = keyboard.nextInt();
}
// count the number of words with the specified length
/* int wordCount = 0;
String word = null;
while ( textScan.hasNext() )
{
word = textScan.next();
if (word.length() == wordLength)
{
wordCount++;
}
}
*/
// prompts the user whether he/she wants a running count of word length - using next() instead of nextLine() to clear buffer
/* System.out.println("Do you want a running total of number of words remaining? ");
String runningTotal = keyboard.next();
if (runningTotal.equalsIgnoreCase("yes"))
System.out.println("Words with that length: " + wordCount);
*/
// create a list (array) of all the words that matches the input length
String word = null;
File file = new File("dictionary.txt");
Scanner textScan = new Scanner(file);
List<String> wordList = new ArrayList<String>();
while ( textScan.hasNext() )
{
word = textScan.next();
wordList.add(word);
}
System.out.println("The ArrayList has " + wordList.size() + " objects stored in it.");
Scanner textScan1 = new Scanner(file);
for(int i = 0; i <= guessNumber; i++)
{
Collections.sort(wordList);
System.out.println("Type in your guess as a letter ");
String guess = keyboard.next();
guess = guess.toLowerCase();
while ( textScan1.hasNext() )
{
String word1 = textScan1.next();
if (wordLength != word1.length() && word1.contains(guess))
{
wordList.remove(word1);
}
}
}
System.out.println("The ArrayList has " + wordList.size() + " objects stored in it.");
System.out.println(wordList);
Finally figured out it had to do with the scanner. It had to be initiated inside the loop
for(int i = 1; i <= guessNumber; i++)
{
Scanner textScan2 = new Scanner(file1);
System.out.println("Type in your guess as a letter ");
String guess = keyboard.next();
//System.out.print(guess);
while ( textScan2.hasNext() )
{
String word1 = textScan2.next();
if (wordLength != word1.length() || (word1.contains(guess)))
{
wordList.remove(word1);
}
}
}
Related
I try to check if characters in a firstname String contain at least 1 digit, if yes ask to the user to input it again and then going back to the loop and check again but with a GoTo break it only works the first time and won't loop it again. Oh and I do this from a method with a String array of more than only a first name in it. Isn't the break GoTo supposed to bring me back to my label and then do the loop over again looking for a digit?
public static void main(String[] args) {
infoInputGathering();
}
public static String[] infoInputGathering(){
String[] infos = new String[3]; // Declaration of the infos String array
boolean isStringOnly;
char[] characterChecker;
Scanner input = new Scanner(System.in); // Creation of the Scanner object input
// Asking the user to input their first name and stores it in a String Array info[0]
System.out.print("Enter your first name: ");
infos[0] = input.next();
characterChecker = infos[0].toCharArray();
firstname:
for (int c = 0 ; c<=characterChecker.length ; ++c ) {
if (Character.isDigit(characterChecker[c])) {
System.out.println("A first name should not contain any number...");
System.out.print("Enter your first name without a number: ");
infos[0] = input.next();
characterChecker = infos[0].toCharArray();
Break firstname;
}
}
Final Full Code I came up with with Ali's help on this part
import java.util.Scanner;
import java.util.ArrayList;
public class InfiniteInfoGatheringUntilStop {
public static void main(String[] args) {
int iterationsCounter = 0; // Declares/Initiate a counter for the loops
Scanner input = new Scanner(System.in); // Creation of the Scanner object input
ArrayList<String> names = new ArrayList<String>(); // Creates an ArrayList for the names inputs
ArrayList<String> birth = new ArrayList<String>(); // Creates an ArrayList for the date of birth inputs
ArrayList<String> gpa = new ArrayList<String>(); // Creates an ArrayList for the GPA inputs
while(true){ // Always true loop unless break out on if conditions
System.out.print("Enter your name: ");
names.add(input.next());
//Code to check if there are numerical character in the String of the listArray inputted
char[] characterChecker = names.get(iterationsCounter).toCharArray(); //Declare and initiates an array of character from the ArrayList names(iterationsCounter)
int c = 0;
while(true){ // Loop to check every character and asks for a retype if detects one character as numerical
if(Character.isDigit(characterChecker[c])){
System.out.println("A first name should not contain any number...");
System.out.print("Enter your first name without a number: ");
names.set(iterationsCounter,input.next());
characterChecker = names.get(iterationsCounter).toCharArray();
c = 0;
}
else {
c++;
}
if(c == characterChecker.length){
break;
}
}
if(names.get(iterationsCounter).equalsIgnoreCase("stop")){ //Checks if stop has been typed, breaks in that case but erases previous ArrayLists of this cycle
names.remove(iterationsCounter);
break;
}
System.out.print("Enter your date of birth in this format AAAAmmdd: ");
birth.add(input.next());
characterChecker = birth.get(iterationsCounter).toCharArray(); //Declare and initiates an array of character from the ArrayList names(iterationsCounter)
c = 0;
while(true){ // Loop to check every character and asks for a retype if detects one character as letter
if(characterChecker.length != 8){ // Checks for a maximum length of 8 characters
System.out.println("A date of birth in the right format (AAAAmmdd) please...");
System.out.print("Reenter your date of birth again (AAAAmmdd): ");
birth.set(iterationsCounter,input.next());
characterChecker = birth.get(iterationsCounter).toCharArray();
}
else if(Character.isLetter(characterChecker[c])){ //checkes if there are letters in the characters
System.out.println("A date of birth in the right format (AAAAmmdd) please...");
System.out.print("Reenter your date of birth again (AAAAmmdd): ");
birth.set(iterationsCounter,input.next());
characterChecker = birth.get(iterationsCounter).toCharArray();
c = 0;
}
else {
c++;
}
if(c == characterChecker.length){ //breaks when c = to the length meaning all characters have been checked through the loop
break;
}
}
if(birth.get(iterationsCounter).equalsIgnoreCase("stop")){ //Checks if stop has been typed, breaks in that case but erases previous ArrayLists of this cycle
names.remove(iterationsCounter);
birth.remove(iterationsCounter);
break;
}
System.out.print("Enter your GPA in 0.0 format: ");
gpa.add(input.next());
characterChecker = gpa.get(iterationsCounter).toCharArray(); //Declare and initiates an array of character from the ArrayList names(iterationsCounter)
c = 0;
while(true){ // Loop to check every character and asks for a retype if detects one character as letter
if(characterChecker.length != 3){ // Checkes for a maximum length of 8 characters
System.out.println("A GPA in the right format please (0.0)...");
System.out.print("Reenter your GPA please: ");
gpa.set(iterationsCounter,input.next());
characterChecker = gpa.get(iterationsCounter).toCharArray();
}
else if(Character.isLetter(characterChecker[c])){ //checks if there are digits in the characters
System.out.println("A GPA in the right format please (0.0)...");
System.out.print("Reenter your GPA: ");
gpa.set(iterationsCounter,input.next());
characterChecker = gpa.get(iterationsCounter).toCharArray();
c = 0;
}
else {
c++;
}
if(c == characterChecker.length){ //breaks when c = to the length meaning all characters have been checked through the loop
break;
}
}
if(gpa.get(iterationsCounter).equalsIgnoreCase("stop")){ //Checks if stop has been typed, breaks in that case but erases previous ArrayLists of this cycle
names.remove(iterationsCounter);
birth.remove(iterationsCounter);
gpa.remove(iterationsCounter);
break;
}
iterationsCounter++; // Incrementes the counter if a full loop is done
}
// Prints the results
System.out.println("Number of valid inputs before you got exhausted: " + iterationsCounter);
System.out.println("====================================================================================");
//A loop to print the content of the 3 ListArrays
for(int arrayLoc = 0; arrayLoc < iterationsCounter; arrayLoc++){
System.out.println((arrayLoc+1) + "-\t" + names.get(arrayLoc) +
"\t\t" + birth.get(arrayLoc) +
"\t\t" + gpa.get(arrayLoc));
}
}
}
You can write your code with while loop like this:
import java.util.Scanner;
public class Test{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String[] infos = new String[3];
char[] characterChecker;
System.out.print("Enter your first name: ");
infos[0] = input.next();
characterChecker = infos[0].toCharArray();
int c = 0;
while(true){
if (Character.isDigit(characterChecker[c])){
System.out.println("A first name should not contain any number...");
System.out.print("Enter your first name without a number: ");
infos[0] = input.next();
characterChecker = infos[0].toCharArray();
c = 0;
}
else
c++;
if(c == characterChecker.length)
break;
}
System.out.println("Correct Name");
}
}
If c is equal to characterChecker.length, ie in the name, there is no number, then it is correct and we break loop and print Correct Name.
This question already has answers here:
Scanner is skipping nextLine() after using next() or nextFoo()?
(24 answers)
Closed 4 years ago.
I was setting up a small app that asks a user to determine the array size and then populate it. The used "for" loop skips the index 0; but I'm uncertain why.
If you run this code with 1 as the array size it skips over the user inputting the first word.
The issue is certainly on the for-loop but it is so simple that I don't see it.
Thanks!
import java.util.Scanner;
public class WordRandomizerAdvanced {
public static void main(String[] args) {
int arrayDimesion;
Scanner sc = new Scanner(System.in);
System.out.println("****************************************************");
System.out.println("******** Welcome to Word Randomizer ADVANCED********");
System.out.println("****************************************************");
//Get array size
System.out.println("How many words would you like to enter?");
arrayDimesion = sc.nextInt();
String[] wordArray = new String[arrayDimesion];
//Populate with user input
for (int i=0; i<arrayDimesion; i++) {
System.out.println("Please enter a word");
wordArray[i] = sc.nextLine();
}
//Print all entered Strings
System.out.println("This are the words you entered: ");
for(int i = 0; i < wordArray.length; i++) {
System.out.println(wordArray[i]);
}
//Print random string from array
int r = (int)(Math.random() * wordArray.length);
System.out.println("The random word is: " + wordArray[r]);
}
}
Change your
arrayDimesion = sc.nextInt();
to
arrayDimesion = Integer.parseInt(sc.nextLine());
Reason: sc.nextInt() doesn't consume the newline character that you give after taking arrayDimesion input. This later on gets consumed in the next sc.nextLine() call.
PS: It might throw NumberFormatException. So you can handle it like :
try {
arrayDimesion = Integer.parseInt(sc.nextLine());
} catch (NumberFormatException e) {
e.printStackTrace();
}
The below code is clean, easy to read and handles the edge cases.
import java.util.Scanner;
public class WordRandomizerAdvanced {
public static void main(String[] args) {
int numOfWords;
Scanner scanner = new Scanner(System.in);
System.out.println("****************************************************");
System.out.println("******** Welcome to Word Randomizer ADVANCED********");
System.out.println("****************************************************");
//Get array size
System.out.println("How many words would you like to enter?");
numOfWords = Integer.parseInt(scanner.nextLine());
String[] wordArray = new String[numOfWords];
//Populate with user input
System.out.println("Please enter the word(s)");
for (int i = 0; i < numOfWords; i++) {
wordArray[i] = scanner.nextLine();
}
//Print all entered Strings
System.out.println("These are the words you entered: ");
for (int i = 0; i < numOfWords; i++) {
System.out.println(wordArray[i]);
}
//Print random string from array
if (numOfWords == 0) {
System.out.println("You didn't enter a word");
} else {
int r = (int) (Math.random() * numOfWords);
System.out.println("The random word is: " + wordArray[r]);
}
}
}
Below is the code that I wrote in order to have a user input a few different strings, check if each is a palindrome, and only return the palindrome. Currently, all of the entered in strings will be returned. It seems that the IF statement if not working correctly. Any suggestions on how to have the correct strings returned?
import java.util.Scanner;
public class hh {
static void checkPalin () {
// creates a scanner
Scanner input = new Scanner(System.in);
int i = 0;
String userInput = "";
// asks the user for the number of strings
System.out.print("Enter the number of strings: ");
StringBuilder sentence = new StringBuilder(userInput);
StringBuilder palindrome = new StringBuilder();
// stores the number of strings user will enters
int stringNumber = input.nextInt();
// prompts the user to enter in their sentences
System.out.println("Enter the strings:");
// this loop will go until the number of strings entered are entered
while(i <= stringNumber){
userInput = input.nextLine();
if(sentence.reverse().equals(sentence)){
palindrome.insert(0, " " + userInput);
}
i ++;
}
// if( sentence == sentence.reverse()){
System.out.println("The palindromes are: " + palindrome);
}
public static void main(String[] args) {
checkPalin();
}
}
You need to create the String from the StringBuilder using the toString method before calling equals:
if(new StringBuilder(userInput).reverse().toString().equals(userInput)) { ... }
When you declare
StringBuilder sentence = new StringBuilder(userInput);
The "sentence" variable will not change if userInput changes. You need to recreate the StringBuilder each time you need it.
Here is the fixed code :
static void checkPalin() {
Scanner input = new Scanner(System.in);
int i = 0;
String userInput = "";
System.out.print("Enter the number of strings: ");
StringBuilder palindrome = new StringBuilder();
int stringNumber = input.nextInt();
System.out.println("Enter the strings:");
while (i <= stringNumber) {
userInput = input.nextLine();
String reversed = new StringBuilder(userInput).reverse().toString();
if (reversed.equals(userInput)) {
palindrome.insert(0, " " + userInput);
}
i++;
}
System.out.println("The palindromes are: " + palindrome);
}
You have to write something like
new StringBuilder(sentence.toString()).reverse().equals(sentence)
in your if
public static void main (String[] args)
{
do {
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter a string: ");
String sentence = keyboard.nextLine();
System.out.print("Enter a letter: ");
String fullLetter = keyboard.nextLine();
char letter = fullLetter.charAt(0);
keyboard.nextLine();
int amount = 0;
for (int i = 0; i < sentence.length(); i++) {
char ch = sentence.charAt(i);
if (ch == letter) {
amount++;
}
}
System.out.println(letter + " appears " + amount + " times in " + sentence);
System.out.print("Continue? ");
String decide = keyboard.nextLine();
} while (decide.equals("yes"));
}
}
I want the user to input either "yes" or "no" at the end of the loop, then I want that input to determine whether or not the program will loop again. As it stands right now, the the last line of my code isn't working. I've looked around and I'm not sure what I should do to fix this.
You need to declare your variable decide outside the loop and initialize inside:
String decide;
do {
//do something ...
decide = keyboard.nextLine();
} while (decide.equals("yes"));
You should use keyboard.next() to read a String instead of keyboard.nextLine()
next() only reads a word, nextLine() reads the whole line including Enter so it will never be equal to "yes"
You must declare declare the string describe outside of the do/while loop, otherwise it is a local variable of the do/while loop, and cannot be accessed by the do testing portion. Simply using
public static void main(String[] args) {
String decide;
do {
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter a string: ");
String sentence = keyboard.nextLine();
System.out.print("Enter a letter: ");
String fullLetter = keyboard.nextLine();
char letter = fullLetter.charAt(0);
keyboard.nextLine();
int amount = 0;
for (int i = 0; i < sentence.length(); i++) {
char ch = sentence.charAt(i);
if (ch == letter) {
amount++;
}
}
System.out.println(letter + " appears " + amount + " times in "
+ sentence);
System.out.print("Continue? ");
decide = keyboard.nextLine();
} while (decide.equals("yes"));
}
will solve your problem.
You has to define your variable decide outside of the loop:
String decide = null
do {
....
decide = keyboard.nextLine();
} while (decide.equals("yes"));
The code works the first time through. But after that, the output doesnt work.
The main goal of this is to create an infinite loop, of asking a user for a phrase, then a letter. Then, to output the number of occurences of the letter in the phrase.
Also - - how would i go about breaking this loop by entering a word?
Scanner in = new Scanner(System.in);
for (;;) {
System.out.println("Enter a word/phrase");
String sentence = in.nextLine();
int times = 0;
System.out.println("Enter a character.");
String letter = in.next();
for (int i = 0; i < sentence.length(); i++) {
char lc = letter.charAt(0);
char sc = sentence.charAt(i);
if (lc == sc) {
times++;
}
}
System.out.print("The character appeared:" + times + " times.");
}
Remove the for loop and replace it with a while.
The while loop should check for a phrase and it will drop out automatically when the phrase is met.
So something like
while (!phraseToCheckFor){
// your code
}
This sounds like homework so I won't post all the code but this should be enough to get you started.
If you need an infinite loop, just do this:
for(;;) { //or while(true) {
//insert code here
}
You can break the loop by using the break statement, for example like this:
for(;;) {
String s = in.nextLine();
if(s.isEmpty()) {
break; //loop terminates here
}
System.out.println(s + " isn't empty.");
}
In order for your program to run correctly, you need to consume the last new line character. You can do this by adding a call to nextLine.
Working example,
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
for (;;) {
System.out.println("Enter a word/phrase");
String sentence = in.nextLine();
if (sentence.trim().equals("quit")) {
break;
}
int times = 0;
System.out.println("Enter a character.");
String letter = in.next();
for (int i = 0; i < sentence.length(); i++) {
char lc = letter.charAt(0);
char sc = sentence.charAt(i);
if (lc == sc) {
times++;
}
}
System.out.println("The character appeared:" + times + " times.");
in.nextLine();//consume the last new line
}
}