I am trying to build something like a hangman (for beginners)
I try this:
int i = 0;
int fails = 0;
boolean success = false;
boolean retval;
char[] defineword = new char[] { 'h', 'u', 'n', 'g' };
char[] givenchar = new char[0];
char[] testchar = new char[] { 'h' };
while (success == false && fails < 5) {
System.out.println("Give a char: ");
String word = input.next(); // INPUT STRING
givenchar = word.toCharArray(); // CONVERT
retval = Arrays.equals(givenchar, testchar);
System.out.println("THE LETTER IS " + retval);
if (retval == true) {
testchar[0] = defineword[i + 1];
} else {
fails++;
}
}
The problem is that it can't continue after the letter ('u'), it is stuck in 'u'.
One observation I will make is that you only real comparison is between givenchar, and testchar.
retval = Arrays.equals(givenchar, testchar);
It would make sense that this wouldn't work once you got past u because testchar never gets past u either. I think you might have intended to add an i++ somewhere.
testchar[0] = defineword[i + 1];
package mer;
import java.util.Scanner;
public class Aswe
{
int i=0;
int f=0;
boolean suc=false;
boolean ret;
char[] dw=new char[]{'h','u','n','g'};
char[] gc=new char[0];
char[] tc=new char[]{'h'};
Scanner i1;
public void me()
{
i1=new Scanner(System.in);
while(suc==false&&f<5)
{
System.out.println("give a char");
String ch=i1.nextLine();
gc=ch.toCharArray();
ret=eual(gc,tc);
System.out.println("the letter is"+ret);
if(ret)
{
tc[0]=dw[i+1];
}
else
f++;
}
}
public boolean eual(char[] a,char[] b)
{
if(a[0]==b[0])
return true;
else
return false;
}
public static void main(String ... args)
{
new Aswe().me();
}
}
private int fails = 0;
private final int maxFails = 5;
private char[] answer = new char[] {'j','a','v','a'};
public Hangman() {
Scanner scan = new Scanner(System.in);
/*
* Game Loop
*/
while(fails < maxFails){
System.out.print("Enter a char: ");
char givenChar = scan.next().charAt(0);
System.out.println("Given char is: " + Check(answer,givenChar));
}
}
/*
* Check if the char exists in the array.
*/
private boolean Check(char[] array,char value){
for(int i = 0; i < array.length; i++){
if(array[i] == value){
return true;
}
}
/*
* Okay did not find any char that match return false.
*/
return false;
}
Related
I've created a wonderfully working program that encrypts the text a person enters with a keyword of their choice. The program can decrypt the encrypted message/text by going in decrypt mode and entering the correct key.
Now my problem is that when I enter a text in the Linux shell that's longer than approximately 5000 characters, it doesn't process all the text. I used this German dummy text that's 15954 characters long. If I enter the text in the Linux shell It cuts off my text at about 4025 characters. On the other hand, if I execute the program in IntelliJ everything works like a charm. If you need the code I got on git here.
Thanks in advance. I appreciate the help.
My Start class that starts everything
public class Start
{
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
System.out.print("Would you like to encrypt or decrypt a message? [d/e]\n>");
char de = scanner.nextLine().charAt(0);
boolean _Encrypt = true;
if (de == 'd')
_Encrypt = false;
else if (de == 'e')
;
else
{
System.out.println("Non valid input. Please try again later.");
System.exit(1);
}
char[] text = ch.wagner.root.viginere.Input.getText("Text:\n>");
char[] key = ch.wagner.root.viginere.Input.getKey("Key:\n>");
if (_Encrypt)
{
System.out.println(ch.wagner.root.viginere.Process.encrypt(text, key));
}
else
{
System.out.println(ch.wagner.root.viginere.Process.decrypt(text, key));
}
}
}
My Input class
public class Input
{
public static char[] getText (String requestMessage)
{
boolean _AllowedToContinue = false;
char[] text = null;
while (!_AllowedToContinue)
{
System.out.print(requestMessage);
text = ch.wagner.root.viginere.Input.getCharArray();
if (!Input.inputValid(new String(text), "[^`^]+$"))
System.out.println("Invalid input. Try again.");
else
_AllowedToContinue = true;
}
// System.err.println(new String(text).length());
// Created this to check the length of the String after input
return text;
}
public static char[] getKey (String requestMessage)
{
boolean _AllowedToContinue = false;
char[] key = null;
while (!_AllowedToContinue)
{
System.out.print(requestMessage);
key = ch.wagner.root.viginere.Input.getCharArray();
if (!Input.inputValid(new String(key), "^[A-Za-z]+$"))
System.out.println("Invalid input. Try again.");
else
_AllowedToContinue = true;
}
return key;
}
private static boolean inputValid (String input, String regex)
{
boolean returnValue = true;
final Pattern pattern = Pattern.compile(regex);
if (!pattern.matcher(input).matches()) {
returnValue = false;
}
return returnValue;
}
private static String getString ()
{
Scanner scanner = new Scanner(System.in);
return scanner.nextLine();
}
private static char[] getCharArray ()
{
return getString().toCharArray();
}
}
The Process class that encrypts/decrypts the text
public class Process
{
public static String decrypt(char[] text, char[] key)
{
int[] shift = new int[key.length];
key = new String(key).toUpperCase().toCharArray();
for (int i = 0; i < shift.length; i++)
shift[i] = key[i] - 65;
int ii = 0;
for (int i = 0; i < text.length; i++)
{
if (ii == shift.length)
ii = 0;
if (Character.isLetter(text[i]))
{
if (((((text[i] - 65) - shift[ii]) % 26) + 65) < 65)
text[i] = (char) (((((text[i] - 65) - shift[ii]) % 26) + 65) + 26);
else
text[i] = (char) ((((text[i] - 65) - shift[ii]) % 26) + 65);
}
ii++;
}
return new String(text);
}
public static String encrypt(char[] text, char[] key)
{
int[] shift = new int[key.length];
key = new String(key).toUpperCase().toCharArray();
for (int i = 0; i < shift.length; i++)
{
shift[i] = key[i] - 65;
}
text = new String(text).replaceAll("[^a-zA-Z0-9|/()*]+", "").toCharArray();
int ii = 0;
for (int i = 0; i < text.length; i++)
{
if (ii == shift.length)
ii = 0;
text[i] = Character.toUpperCase(text[i]);
if (Character.isLetter(text[i]))
text[i] = (char)((((text[i] - 65) + shift[ii]) % 26) + 65);
ii++;
}
return new String(text);
}
}
This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 7 years ago.
So this program is supposed to be a game where a user enters a phrase and another user tries to guess the phrase. I'm having a problem with buying a vowel, however. No matter what I enter at line 41 (, it just goes past the loop. I made the validAnswer(String answer) method in the hopes that it would be useful in the loop but it doesn't look to be much help. I know there is a small thing I'm missing but I'm too new to Java to recognize it yet. What am I doing wrong?
I apologize for the long amount of code.
import java.util.Scanner;
public class PhraseGame {
public static void main(String[] args) {
// Initialize scanner
Scanner stdIn = new Scanner(System.in);
// Initialize variables
String sPhrase;
String answer = "f";
char cGuess = 0;
char vGuess = 0;
int count = 0;
int vowels = 0;
int consonants = 0;
int spaces = 0;
boolean gameOver = false;
boolean correct = true;
// Start the "fun" game
System.out.print("Please enter the phrase to guess at: ");
sPhrase = stdIn.nextLine();
// Create the temporary Array
char [] tmpArr = new char[sPhrase.length()];
for (int i = 0; i < sPhrase.length(); i++) {
tmpArr[i] = sPhrase.charAt(i);
}
// Gets the number of spaces
spaces = initTemplateArray(sPhrase, tmpArr, spaces);
printTemplateArray(tmpArr);
while (!(endGame(gameOver, spaces, consonants, vowels, sPhrase))) {
cGuess = getConsonant(stdIn, cGuess);
do {
System.out.print("\nWould you like to buy a vowel?: ");
answer = stdIn.next();
if (answer == "y") {
getVowel(stdIn, vGuess); }
else if (answer == "n"){
break;
}
} while (!validAnswer(answer));
// Updates the array and prints it
updateTemplateArray(tmpArr, sPhrase, cGuess, vGuess, count, vowels, consonants);
printTemplateArray(tmpArr);
// Checks if the game is over
endGame(gameOver, spaces, consonants, vowels, sPhrase);
}
}
// returns the number of space characters used in the common phrase
public static int initTemplateArray(String sPhrase, char [] tmpArr, int spaces) {
for (int i = 0; i < sPhrase.length(); i++) {
if (tmpArr[i] != ' ') {
tmpArr[i] = '?';
} else {
tmpArr[i] = ' ';
spaces++;
}
}
return spaces;
}
public static void printTemplateArray(char [] tmpArr) {
System.out.println("\nCommon Phrase");
System.out.println("-------------");
for (int i = 0; i < tmpArr.length; i++) {
System.out.print(tmpArr[i]);
}
}
public static boolean isVowel(char c) {
return (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u');
}
public static char getConsonant(Scanner stdIn, char cGuess) {
do {
System.out.println("\nEnter a lowercase consonant guess: ");
cGuess = stdIn.next().charAt(0);
} while (isVowel(cGuess));
return cGuess;
}
public static char getVowel(Scanner stdIn, char vGuess) {
do {
System.out.println("\nEnter a lowercase vowel guess: ");
vGuess = stdIn.next().charAt(0);
} while (!(isVowel(vGuess)));
return vGuess;
}
public static int updateTemplateArray(char [] tmpArr, String sPhrase, char cGuess, char vGuess, int count, int vowels, int consonants) {
for (int i = 0; i < sPhrase.length(); i++) {
if (cGuess == sPhrase.charAt(i)) {
tmpArr[i] = sPhrase.charAt(i);
count++;
consonants++;
}
if (vGuess == sPhrase.charAt(i)) {
tmpArr[i] = sPhrase.charAt(i);
count++;
vowels++;
}
}
return count & vowels & consonants;
}
public static boolean endGame(boolean gameOver, int spaces, int consonants, int vowels, String sPhrase) {
int total = spaces + consonants + vowels;
if (total == sPhrase.length()) {
return true;
}
else {
return false;
}
}
public static boolean validAnswer(String answer) {
if (answer.equalsIgnoreCase("y")) {
return true;
}
else if (answer.equalsIgnoreCase("n")) {
return true;
}
else {
return false;
}
}
}
You need to check for null.
public static boolean validAnswer(String answer) {
if (answer!=null && (answer.equalsIgnoreCase("y") || answer.equalsIgnoreCase("n"))) {
return true;
}
return false;
}
or an other unconventional way.
public static boolean validAnswer(String answer) {
if ("y".equalsIgnoreCase(answer) || "n".equalsIgnoreCase(answer))) {
return true;
}
return false;
}
You need to fix
do {
System.out.print("\nWould you like to buy a vowel?: ");
answer = stdIn.nextLine();
if ("y".equalsIgnoreCase(answer)) {
getVowel(stdIn, vGuess);
} else if ("n".equalsIgnoreCase(answer)){
break;
}
} while (!validAnswer(answer));
I have a Java Assignment where I have to prompt for a line input, check if its a palindrome and then say if the palindrome is made of all text, all numbers, or mixed. I haven't added the part where I check what kind of palindrome it is yet, but I need help with the code to check if it's a palindrome. The code I posted below recognizes everything as a palindrome even if it isn't. This is basic Java so I'm limited to what I used below.
import java.util.Scanner;
public class Project4{
public static void main (String [] args)
{
String line = getInputLine();
while (!isEmptyLine (line))
{
if (isPalindrome (line))
System.out.println ("\"" + line + "\" is a palindrome.");
else
System.out.println ("\"" + line + "\" is not a palindrome");
line = getInputLine();
}
System.out.println ("End of program");
}
public static String getInputLine ( )
{
Scanner in = new Scanner(System.in);
System.out.print("Enter a line of input: ");
String inputline = in.nextLine();
return inputline;
}
public static boolean isEmptyLine(String str)
{
boolean truefalse;
if(str.length()==0)
truefalse = true;
else
truefalse = false;
return truefalse;
}
public static boolean isPalindrome(String str)
{
int left = 0;
int right = str.length();
boolean okay = true;
char ch1; char ch2;
while(okay && left<right)
{
ch1 = str.charAt(left);
if(!Character.isDigit(ch1)||!Character.isLetter(ch1))
left++;
else
{
ch2 = str.charAt(right);
if(!Character.isDigit(ch2)||!Character.isLetter(ch2))
right--;
else
{
ch1 = Character.toUpperCase(ch1);
ch2 = Character.toUpperCase(ch2);
if(ch1==ch2)
{
left++;
right--;
}
else
okay = false;
}
}
}
return okay;
}
}
You need to do logical AND of the 2 checks instead of OR -
if(!Character.isDigit(ch1) && !Character.isLetter(ch1))
Use a method like the following:
boolean isPalindrome (String input) {
int strLength = input.length;
for (int i=0; i < input.length/2; ++i) {
if (input.charAt(i) != input.charAt(strLength-i)) {
return false;
}
}
return true;
}
A late answer although it might help some in the future. The method posted below doesn't use any of StringBuilder functions.
public boolean isPalindrome(String value) {
boolean isPalindrome = true;
for (int i = 0 , j = value.length() - 1 ; i < j ; i ++ , j --) {
if (value.charAt(i) != value.charAt(j)) {
isPalindrome = false;
}
}
return isPalindrome;
}
i was wondering how can i create a method where i can get the single instance from a string and give it a numericValue for example, if theres a String a = "Hello what the hell" there are 4 l characters and i want to give a substring from the String a which is Hello and give it numeric values. Right now in my program it gets all the character instances from string so the substring hello would get number values from the substring hell too because it also has the same characters.
my code :
public class Puzzle {
private static char[] letters = {'a','b','c','d','e','f','g','h','i', 'j','k','l','m','n','o','p','q','r','s',
't','u','v','w','x','y','z'};
private static String input;
private static String delimiters = "\\s+|\\+|//+|=";
public static void main(String[]args)
{
input = "help + me = please";
System.out.println(putValues(input));
}
//method to put numeric values for substring from input
#SuppressWarnings("static-access")
public static long putValues(String input)
{
Integer count;
long answer = 0;
String first="";
String second = "";
StringBuffer sb = new StringBuffer(input);
int wordCounter = Countwords();
String[] words = countLetters();
System.out.println(input);
if(input.isEmpty())
{
System.out.println("Sisestage mingi s6na");
}
if(wordCounter == -1 ||countLetters().length < 1){
return -1;
}
for(Character s : input.toCharArray())
{
for(Character c : letters)
{
if(s.equals(c))
{
count = c.getNumericValue(c) - 9;
System.out.print(s.toUpperCase(s) +"="+ count + ", ");
}
}
if(words[0].contains(s.toString()))
{
count = s.getNumericValue(s);
//System.out.println(count);
first += count.toString();
}
if(words[3].contains(s.toString())){
count = s.getNumericValue(s);
second += count.toString();
}
}
try {
answer = Long.parseLong(first)+ Long.parseLong(second);
} catch(NumberFormatException ex)
{
System.out.println(ex);
}
System.out.println("\n" + first + " + " + second + " = " + answer);
return answer;
}
public static int Countwords()
{
String[] countWords = input.split(" ");
int counter = countWords.length - 2;
if(counter == 0) {
System.out.println("Sisend puudu!");
return -1;
}
if(counter > 1 && counter < 3) {
System.out.println("3 sõna peab olema");
return -1;
}
if(counter > 3) {
System.out.println("3 sõna max!");
return -1;
}
return counter;
}
//method which splits input String and returns it as an Array so i can put numeric values after in the
//putValue method
public static String[] countLetters()
{
int counter = 0;
String[] words = input.split(delimiters);
for(int i = 0; i < words.length;i++) {
counter = words[i].length();
if(words[i].length() > 18) {
System.out.println("One word can only be less than 18 chars");
}
}
return words;
}
Program has to solve the word puzzles where you have to guess which digit corresponds to which letter to make a given equality valid. Each letter must correspond to a different decimal digit, and leading zeros are not allowed in the numbers.
For example, the puzzle SEND+MORE=MONEY has exactly one solution: S=9, E=5, N=6, D=7, M=1, O=0, R=8, Y=2, giving 9567+1085=10652.
import java.util.ArrayList;
public class main {
private static String ChangeString;
private static String[] ArrayA;
private static String a;
private static int wordnumber;
private static String temp;
public static void main(String[] args) {
// TODO Auto-generated method stub
a = "hello what the hell";
wordnumber = 0;
identifyint(a,wordnumber);
}
public static void identifyint (String a, int WhichWord){
ChangeString = a.split(" ")[WhichWord];
ArrayA = a.split(" ");
replaceword();
ArrayA[wordnumber] = ChangeString;
//System.out.print(ArrayA[wordnumber]);
a = "";
for(int i = 0; i<ArrayA.length;i++){
if(i==wordnumber){
a = a.concat(temp+ " ");
}
else{
a = a.concat(ArrayA[i]+" ");
}
}
System.out.print(a);
}
public static void replaceword(){
temp = "";
Character arr[] = new Character[ChangeString.length()];
for(int i = 0; i<ChangeString.length();i++){
arr[i] = ChangeString.charAt(i);
Integer k = arr[i].getNumericValue(arr[i])-9;
temp = temp.concat(""+k);
}
a = temp;
}
}
Change wordnumber to the word you want to replace each time. If this is not what you have asked for, please explain your question in more detail.
In my program, the user enters a string, and it first finds the largest mode of characters in the string. Next, my program is supposed to remove all duplicates of a character in a string, (user input: aabc, program prints: abc) which I'm not entirely certain on how to do. I can get it to remove duplicates from some strings, but not all. For example, when the user puts "aabc" it will print "abc", but if the user puts "aabbhh", it will print "abbhh." Also, before I added the removeDup method to my program, it would only print the maxMode once, but after I added the removeDup method, it began to print the maxMode twice. How do I keep it from printing it twice?
Note: I cannot convert the strings to an array.
import java.util.Scanner;
public class JavaApplication3 {
static class MyStrings {
String s;
void setMyStrings(String str) {
s = str;
}
int getMode() {
int i;
int j;
int count = 0;
int maxMode = 0, maxCount = 1;
for (i = 0; i< s.length(); i++) {
maxCount = count;
count = 0;
for (j = s.length()-1; j >= 0; j--) {
if (s.charAt(j) == s.charAt(i))
count++;
if (count > maxCount){
maxCount = count;
maxMode = i;
}
}
}
System.out.println(s.charAt(maxMode)+" = largest mode");
return maxMode;
}
String removeDup() {
getMode();
int i;
int j;
String rdup = "";
for (i = 0; i< s.length(); i++) {
int count = 1;
for (j = 0; j < rdup.length(); j++) {
if (s.charAt(i) == s.charAt(j)){
count++;
}
}
if (count == 1){
rdup += s.charAt(i);
}
}
System.out.print(rdup);
System.out.println();
return rdup;
}
}
public static void main (String[] args) {
Scanner in = new Scanner(System.in);
MyStrings setS = new MyStrings();
String s;
System.out.print("Enter string:");
s = in.nextLine();
setS.setMyStrings(s);
setS.getMode();
setS.removeDup();
}
}
Try this method...should work fine!
String removeDup()
{
getMode();
int i;
int j;
String rdup = "";
for (i = 0; i< s.length(); i++) {
int count = 1;
for (j = i+1; j < s.length(); j++) {
if (s.charAt(i) == s.charAt(j)) {
count++;
}
}
if (count == 1){
rdup += s.charAt(i);
}
}
// System.out.print(rdup);
System.out.println();
return rdup;
}
Welcome to StackOverflow!
You're calling getMode() both outside and inside of removeDup(), which is why it's printing it twice.
In order to remove all duplicates, you'll have to call removeDup() over and over until all the duplicates are gone from your string. Right now you're only calling it once.
How might you do that? Think about how you're detecting duplicates, and use that as the end condition for a while loop or similar.
Happy coding!
Shouldn't this be an easier way? Also, i'm still learning.
import java.util.*;
public class First {
public static void main(String arg[])
{
Scanner sc= new Scanner(System.in);
StringBuilder s=new StringBuilder(sc.nextLine());
//String s=new String();
for(int i=0;i<s.length();i++){
String a=s.substring(i, i+1);
while(s.indexOf(a)!=s.lastIndexOf(a)){s.deleteCharAt(s.lastIndexOf(a));}
}
System.out.println(s.toString());
}
}
You can do this:
public static void main(String[] args) {
String str = new String("PINEAPPLE");
Set <Character> letters = new <Character>HashSet();
for (int i = 0; i < str.length(); i++) {
letters.add(str.charAt(i));
}
System.out.println(letters);
}
I think an optimized version which supports ASCII codes can be like this:
public static void main(String[] args) {
System.out.println(removeDups("*PqQpa abbBBaaAAzzK zUyz112235KKIIppP!!QpP^^*Www5W38".toCharArray()));
}
public static String removeDups(char []input){
long ocr1=0l,ocr2=0l,ocr3=0;
int index=0;
for(int i=0;i<input.length;i++){
int val=input[i]-(char)0;
long ocr=val<126?val<63?ocr1:ocr2:ocr3;
if((ocr& (1l<<val))==0){//not duplicate
input[index]=input[i];
index++;
}
if(val<63)
ocr1|=(1l<<val);
else if(val<126)
ocr2|=(1l<<val);
else
ocr3|=(1l<<val);
}
return new String(input,0,index);
}
please keep in mind that each of orc(s) represent a mapping of a range of ASCII characters and each java long variable can grow as big as (2^63) and since we have 128 characters in ASCII so we need three ocr(s) which basically maps the occurrences of the character to a long number.
ocr1: (char)0 to (char)62
ocr2: (char)63 to (char)125
ocr3: (char)126 to (char)128
Now if a duplicate was found the
(ocr& (1l<<val))
will be greater than zero and we skip that char and finally we can create a new string with the size of index which shows last non duplicate items index.
You can define more orc(s) and support other character-sets if you want.
Can use HashSet as well as normal for loops:
public class RemoveDupliBuffer
{
public static String checkDuplicateNoHash(String myStr)
{
if(myStr == null)
return null;
if(myStr.length() <= 1)
return myStr;
char[] myStrChar = myStr.toCharArray();
HashSet myHash = new HashSet(myStrChar.length);
myStr = "";
for(int i=0; i < myStrChar.length ; i++)
{
if(! myHash.add(myStrChar[i]))
{
}else{
myStr += myStrChar[i];
}
}
return myStr;
}
public static String checkDuplicateNo(String myStr)
{
// null check
if (myStr == null)
return null;
if (myStr.length() <= 1)
return myStr;
char[] myChar = myStr.toCharArray();
myStr = "";
int tail = 0;
int j = 0;
for (int i = 0; i < myChar.length; i++)
{
for (j = 0; j < tail; j++)
{
if (myChar[i] == myChar[j])
{
break;
}
}
if (j == tail)
{
myStr += myChar[i];
tail++;
}
}
return myStr;
}
public static void main(String[] args) {
String myStr = "This is your String";
myStr = checkDuplicateNo(myStr);
System.out.println(myStr);
}
Try this simple answer- works well for simple character string accepted as user input:
import java.util.Scanner;
public class string_duplicate_char {
String final_string = "";
public void inputString() {
//accept string input from user
Scanner user_input = new Scanner(System.in);
System.out.println("Enter a String to remove duplicate Characters : \t");
String input = user_input.next();
user_input.close();
//convert string to char array
char[] StringArray = input.toCharArray();
int StringArray_length = StringArray.length;
if (StringArray_length < 2) {
System.out.println("\nThe string with no duplicates is: "
+ StringArray[1] + "\n");
} else {
//iterate over all elements in the array
for (int i = 0; i < StringArray_length; i++) {
for (int j = i + 1; j < StringArray_length; j++) {
if (StringArray[i] == StringArray[j]) {
int temp = j;//set duplicate element index
//delete the duplicate element by copying the adjacent elements by one place
for (int k = temp; k < StringArray_length - 1; k++) {
StringArray[k] = StringArray[k + 1];
}
j++;
StringArray_length--;//reduce char array length
}
}
}
}
System.out.println("\nThe string with no duplicates is: \t");
//print the resultant string with no duplicates
for (int x = 0; x < StringArray_length; x++) {
String temp= new StringBuilder().append(StringArray[x]).toString();
final_string=final_string+temp;
}
System.out.println(final_string);
}
public static void main(String args[]) {
string_duplicate_char object = new string_duplicate_char();
object.inputString();
}
}
Another easy solution to clip the duplicate elements in a string using HashSet and ArrayList :
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Scanner;
public class sample_work {
public static void main(String args[]) {
String input = "";
System.out.println("Enter string to remove duplicates: \t");
Scanner in = new Scanner(System.in);
input = in.next();
in.close();
ArrayList<Character> String_array = new ArrayList<Character>();
for (char element : input.toCharArray()) {
String_array.add(element);
}
HashSet<Character> charset = new HashSet<Character>();
int array_len = String_array.size();
System.out.println("\nLength of array = " + array_len);
if (String_array != null && array_len > 0) {
Iterator<Character> itr = String_array.iterator();
while (itr.hasNext()) {
Character c = (Character) itr.next();
if (charset.add(c)) {
} else {
itr.remove();
array_len--;
}
}
}
System.out.println("\nThe new string with no duplicates: \t");
for (int i = 0; i < array_len; i++) {
System.out.println(String_array.get(i).toString());
}
}
}
your can use this simple code and understand how to remove duplicates values from string.I think this is the simplest way to understand this problem.
class RemoveDup
{
static int l;
public String dup(String str)
{
l=str.length();
System.out.println("length"+l);
char[] c=str.toCharArray();
for(int i=0;i<l;i++)
{
for(int j=0;j<l;j++)
{
if(i!=j)
{
if(c[i]==c[j])
{
l--;
for(int k=j;k<l;k++)
{
c[k]=c[k+1];
}
j--;
}
}
}
}
System.out.println("after concatination lenght:"+l);
StringBuilder sd=new StringBuilder();
for(int i=0;i<l;i++)
{
sd.append(c[i]);
}
str=sd.toString();
return str;
}
public static void main(String[] ar)
{
RemoveDup obj=new RemoveDup();
Scanner sc=new Scanner(System.in);
String st,t;
System.out.println("enter name:");
st=sc.nextLine();
sc.close();
t=obj.dup(st);
System.out.println(t);
}
}
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package javaapplication26;
import java.util.*;
/**
*
* #author THENNARASU
*/
public class JavaApplication26 {
public static void main(String[] args) {
int i,j,k=0,count=0,m;
char a[]=new char[10];
char b[]=new char[10];
Scanner ob=new Scanner(System.in);
String str;
str=ob.next();
a=str.toCharArray();
int c=str.length();
for(j=0;j<c;j++)
{
for(i=0;i<j;i++)
{
if(a[i]==a[j])
{
count=1;
}
}
if(count==0)
{
b[k++]=a[i];
}
count=0;
}
for(m=0;b[m]!='\0';m++)
{
System.out.println(b[m]);
}
}
}
i wrote this program. Am using 2 char arrays instead. You can define the number of duplicate chars you want to eliminate from the original string and also shows the number of occurances of each character in the string.
public String removeMultipleOcuranceOfChar(String string, int numberOfChars){
char[] word1 = string.toCharArray();
char[] word2 = string.toCharArray();
int count=0;
StringBuilder builderNoDups = new StringBuilder();
StringBuilder builderDups = new StringBuilder();
for(char x: word1){
for(char y : word2){
if (x==y){
count++;
}//end if
}//end inner loop
System.out.println(x + " occurance: " + count );
if (count ==numberOfChars){
builderNoDups.append(x);
}else{
builderDups.append(x);
}//end if else
count = 0;
}//end outer loop
return String.format("Number of identical chars to be in or out of input string: "
+ "%d\nOriginal word: %s\nWith only %d identical chars: %s\n"
+ "without %d identical chars: %s",
numberOfChars,string,numberOfChars, builderNoDups.toString(),numberOfChars,builderDups.toString());
}
Try this simple solution for REMOVING DUPLICATE CHARACTERS/LETTERS FROM GIVEN STRING
import java.util.Scanner;
public class RemoveDuplicateLetters {
public static void main(String[] args) {
Scanner scn=new Scanner(System.in);
System.out.println("enter a String:");
String s=scn.nextLine();
String ans="";
while(s.length()>0)
{
char ch = s.charAt(0);
ans+= ch;
s = s.replace(ch+"",""); //Replacing all occurrence of the current character by a spaces
}
System.out.println("after removing all duplicate letters:"+ans);
}
}
In Java 8 we can do that using
private void removeduplicatecharactersfromstring() {
String myString = "aabcd eeffff ghjkjkl";
StringBuilder builder = new StringBuilder();
Arrays.asList(myString.split(" "))
.forEach(s -> {
builder.append(Stream.of(s.split(""))
.distinct().collect(Collectors.joining()).concat(" "));
});
System.out.println(builder); // abcd ef ghjkl
}