It is necessary to repeat the character, as many times as the number behind it.
They are positive integer numbers.
case #1
input: "abc3leson11"
output: "abccclesonnnnnnnnnnn"
I already finish it in the following way:
String a = "abbc2kd3ijkl40ggg2H5uu";
String s = a + "*";
String numS = "";
int cnt = 0;
for (int i = 0; i < s.length(); i++) {
char ch = s.charAt(i);
if (Character.isDigit(ch)) {
numS = numS + ch;
cnt++;
} else {
cnt++;
try {
for (int j = 0; j < Integer.parseInt(numS); j++) {
System.out.print(s.charAt(i - cnt));
}
if (i != s.length() - 1 && !Character.isDigit(s.charAt(i + 1))) {
System.out.print(s.charAt(i));
}
} catch (Exception e) {
if (i != s.length() - 1 && !Character.isDigit(s.charAt(i + 1))) {
System.out.print(s.charAt(i));
}
}
cnt = 0;
numS = "";
}
}
But I wonder is there some better solution with less and cleaner code?
Could you take a look below? I'm using a library from StringUtils from Apache Common Utils to repeat character:
public class MicsTest {
public static void main(String[] args) {
String input = "abc3leson11";
String output = input;
Pattern p = Pattern.compile("\\d+");
Matcher m = p.matcher(input);
while (m.find()) {
int number = Integer.valueOf(m.group());
char repeatedChar = input.charAt(m.start()-1);
output = output.replaceFirst(m.group(), StringUtils.repeat(repeatedChar, number));
}
System.out.println(output);
}
}
In case you don't want to use StringUtils. You can use the below custom method to achieve the same effect:
public static String repeat(char c, int times) {
char[] chars = new char[times];
Arrays.fill(chars, c);
return new String(chars);
}
Using java basic string regx should make it more terse as follows:
public class He1 {
private static final Pattern pattern = Pattern.compile("[a-zA-Z]+(\\d+).*");
// match the number between or the last using regx;
public static void main(String... args) {
String s = "abc3leson11";
System.out.println(parse(s));
s = "abbc2kd3ijkl40ggg2H5uu";
System.out.println(parse(s));
}
private static String parse(String s) {
Matcher matcher = pattern.matcher(s);
while (matcher.find()) {
int num = Integer.valueOf(matcher.group(1));
char prev = s.charAt(s.indexOf(String.valueOf(num)) - 1);
// locate the char before the number;
String repeated = new String(new char[num-1]).replace('\0', prev);
// since the prev is not deleted, we have to decrement the repeating number by 1;
s = s.replaceFirst(String.valueOf(num), repeated);
matcher = pattern.matcher(s);
}
return s;
}
}
And the output should be:
abccclesonnnnnnnnnnn
abbcckdddijkllllllllllllllllllllllllllllllllllllllllggggHHHHHuu
String g(String a){
String result = "";
String[] array = a.split("(?<=\\D)(?=\\d)|(?<=\\d)(?=\\D)");
//System.out.println(java.util.Arrays.toString(array));
for(int i=0; i<array.length; i++){
String part = array[i];
result += part;
if(++i == array.length){
break;
}
char charToRepeat = part.charAt(part.length() - 1);
result += repeat(charToRepeat+"", new Integer(array[i]) - 1);
}
return result;
}
// In Java 11 this could be removed and replaced with the builtin `str.repeat(amount)`
String repeat(String str, int amount){
return new String(new char[amount]).replace("\0", str);
}
Try it online.
Explanation:
The split will split the letters and numbers:
abbc2kd3ijkl40ggg2H5uu would become ["abbc", "2", "kd", "3", "ijkl", "40", "ggg", "2", "H", "5", "uu"]
We then loop over the parts and add any strings as is to the result.
We then increase i by 1 first and if we're done (after the "uu") in the array above, it will break the loop.
If not the increase of i will put us at a number. So it will repeat the last character of the part x amount of times, where x is the number we found minus 1.
Here is another solution:
String str = "abbc2kd3ijkl40ggg2H5uu";
String[] part = str.split("(?<=\\d)(?=\\D)|(?=\\d)(?<=\\D)");
String res = "";
for(int i=0; i < part.length; i++){
if(i%2 == 0){
res = res + part[i];
}else {
res = res + StringUtils.repeat(part[i-1].charAt(part[i-1].length()-1),Integer.parseInt(part[i])-1);
}
}
System.out.println(res);
Yet another solution :
public static String getCustomizedString(String input) {
ArrayList<String > letters = new ArrayList<>(Arrays.asList(input.split("(\\d)")));
letters.removeAll(Arrays.asList(""));
ArrayList<String > digits = new ArrayList<>(Arrays.asList(input.split("(\\D)")));
digits.removeAll(Arrays.asList(""));
for(int i=0; i< digits.size(); i++) {
int iteration = Integer.valueOf(digits.get(i));
String letter = letters.get(i);
char c = letter.charAt(letter.length()-1);
for (int j = 0; j<iteration -1 ; j++) {
letters.set(i,letters.get(i).concat(String.valueOf(c)));
}
}
String finalResult = "";
for (String str : letters) {
finalResult += str;
}
return finalResult;
}
The usage:
public static void main(String[] args) {
String testString1 = "abbc2kd3ijkl40ggg2H5uu";
String testString2 = "abc3leson11";
System.out.println(getCustomizedString(testString1));
System.out.println(getCustomizedString(testString2));
}
And the result:
abbcckdddijkllllllllllllllllllllllllllllllllllllllllggggHHHHHuu
abccclesonnnnnnnnnnn
I'm trying to create a method that replace all instances of a certain character in a word with a new character. This is what I have so far:
public class practice {
public static void main(String[] args) {
String test3 = updatePartialword("----", "test", 't');
System.out.println(test3); }
public static String updatePartialword(String partial, String secret, char c) {
String newPartial = "";
int len = secret.length();
for (int i=0; i<=secret.length()-1; i++){
char x = secret.charAt(i);
if (c==x) {
String first = partial.substring(0,i);
String second = partial.substring(i+1,len);
newPartial = first+x+second;
}
}
return newPartial;
}
}
I want it to return t--t, but it will only print the last t. Any help would be greatly appreciated!
Java already has a built in method in String for this. You can use the the replace() method to replace all occurrences of the given character in the String with the another character
String str = "Hello";
str.replace('l', '-'); //Returns He--o
str.replace('H', '-'); //Returns -ello
I suspect you are looking for something like
public static void main(String[] args) {
String test3 = updatePartialword("----", "test", 't');
System.out.println(test3);
}
public static String updatePartialword(String partial, String secret, char c) {
char[] tmp = partial.toCharArray();
for (int i = 0; i < secret.length(); i++) {
char x = secret.charAt(i);
if (c == x) {
tmp[i] = c;
}
}
return new String(tmp);
}
In your code you overwrite the String each time you found the character. Instead of overwriting, you should expand the string each time.
public class practice {
public static void main(String[] args) {
String test3 = updatePartialword("----", "test", 't');
System.out.println(test3);
}
public static String updatePartialword(String partial, String secret, char c) {
StringBuilder sb = new Stringbuilder();
sb.append(""); // to prevent the Stringbuilder from calculating with the chars
for (int i = 0; i < partial.lenght; i++)
if (secret.charAt(i) == c)
sb.append(c);
else
sb.append('-');
return sb.toString();
}
}
Assuming I have a string foo = "This is an apple"
The Unicode code point equivalent will be
" \\x74\\x68\\x69\\x73.......... \\x61\\x70\\x70\\x6c\\x65 "
T h i s ............. a p p l e
How do I convert from String foo
to
String " \\x74\\x68\\x69\\x73.......... \\x61\\x70\\x70\\x6c\\x65 "
try this..
public static String generateUnicode(String input) {
StringBuilder b = new StringBuilder(input.length());
for (char c : input.toCharArray()) {
b.append(String.format("\\u%04x", (int) c));
}
return b.toString();
}
Here a working code snippet to make the conversion:
public class HexTest {
public static void main(String[] args) {
String testStr = "hello日本語 ";
System.out.println(stringToUnicode3Representation(testStr));
}
private static String stringToUnicode3Representation(String str) {
StringBuilder result = new StringBuilder();
char[] charArr = str.toCharArray();
for (int i = 0; i < charArr.length; i++) {
result.append("\\u").append(Integer.toHexString(charArr[i] | 0x10000).substring(1));
}
return result.toString();
}
}
That display:
\u0068\u0065\u006c\u006c\u006f\u65e5\u672c\u8a9e\u0020
If you want to get rid of the extra zeros you elaborate it as described here.
Here another version to do the conversion, by passing "This is an apple" you get
\u54\u68\u69\u73\u20\u69\u73\u20\u61\u6e\u20\u61\u70\u70\u6c\u65
by using:
private static String str2UnicodeRepresentation(String str) {
StringBuilder result = new StringBuilder();
for (int i = 0; i < str.length(); i++) {
int cp = Character.codePointAt(str, i);
int charCount = Character.charCount(cp);
//UTF characters may use more than 1 char to be represented
if (charCount == 2) {
i++;
}
result.append(String.format("\\u%x", cp));
}
return result.toString();
}
i have to do a program which takes a sentence and reverses it word by word in java. for eg:
India is my country
output:aidnI si ym yrtnuoc
ive figured out all of it but i just cant split a sentence into separate words.im not allowed to use split function but im meant to use either substring or indexof();while loop and for loop are allowed.
this is what ive got so far:
import java.io.*;
public class Rereprogram10
{
public void d()throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
String str;
System.out.println("input a string");
str=br.readLine();
String rev="";
int length=str.length();
int counter=length;
for(int i=0;i<length;i++)
{
rev=rev+str.charAt(counter-1);
counter--;
}
System.out.println("the result is: "+rev);
}
}
its wrong though,the output keeps on coming:
yrtnuoc ym si aidnI
i havent learnt arrays yet...
I'm going to assume that advanced datastructures are out, and efficiency is not an issue.
Where you are going wrong is that you are reversing the entire string, you need to only reverse the words. So you really need to check to find where a word ends, then either reverse it then, or be reversing it as you go along.
Here is an example of reversing as you go along.
int length=str.length();
String sentence="";
String word = "";
for(int i=0;i<length;i++) {
if (str.charAt(i) != ' '){
word = str.charAt(i) + word;
} else {
sentence += word +" ";
word = "";
}
}
sentence += word;
System.out.println("the result is: "+sentence);
This passes the test:
package com.sandbox;
import com.google.common.base.Joiner;
import org.junit.Test;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import static org.junit.Assert.assertEquals;
public class SandboxTest {
#Test
public void testQuestionInput() {
String input = "India is my country";
assertEquals("country my is India", reverseWords(input));
}
private String reverseWords(String input) {
List<String> words = putWordsInList(input);
Collections.reverse(words);
return Joiner.on(" ").join(words);
}
private List<String> putWordsInList(String input) {
List<String> words = new ArrayList<String>();
String word = "";
for (int i = 0; i < input.length(); i++) {
char c = input.charAt(i);
if (c == ' ') {
words.add(word);
word = "";
} else {
word += c;
}
}
words.add(word);
return words;
}
}
Here is my code without split() for you.
Input:
India is my country
Output:
country my is India
aidnI si ym yrtnuoc
You can choose the output you need.
public class Reverse {
public static class Stack {
private Node[] slot = new Node[1000];
private int pos = 0;
private class Node{
private char[] n = new char[30];
private int pos = 0;
public void push(char c) {
n[pos++] = c;
}
public String toString() {
return new String(n).trim() + " "; // TODO Fix
}
}
public void push(char c) {
if(slot[pos] == null)
slot[pos] = new Node();
if(c != ' ') {
slot[pos].push(c);
} else {
slot[pos++].push(c);
}
}
public String toString() {
StringBuilder sb = new StringBuilder();
for(int i = pos; i >=0; i --)
sb.append(slot[i]);
return sb.toString();
}
private String reverseWord(String word) {
StringBuilder sb = new StringBuilder();
int len = word.length();
for(int i = len - 1; i >= 0; i--)
sb.append(word.charAt(i));
return sb.toString();
}
public String foryou() {
StringBuilder sb = new StringBuilder();
for(int i = 0; i < pos + 1; i ++)
sb.append(this.reverseWord(slot[i].toString()));
return sb.toString();
}
}
/**
* #param args
*/
public static void main(String[] args) {
Stack stack = new Stack();
String sentence = "India is my country";
System.out.println(sentence);
for(int i = 0; i < sentence.length(); i ++) {
stack.push(sentence.charAt(i));
}
System.out.println(stack);
System.out.println(stack.foryou());
}
}
try this
String x="India is my country";
StringBuilder b=new StringBuilder();
int i=0;
do{
i=x.indexOf(" ", 0);
String z;
if(i>0){
z=x.substring(0,i);
}
else{
z=x;
}
x=x.substring(i+1);
StringBuilder v=new StringBuilder(z);
b.append(v.reverse());
if(i!=-1)
b.append(" ");
System.out.println(b.toString());
}
while(i!=-1);
I want to split string without using split . can anybody solve my problem I am tried but
I cannot find the exact logic.
Since this seems to be a task designed as coding practice, I'll only guide. No code for you, sir, though the logic and the code aren't that far separated.
You will need to loop through each character of the string, and determine whether or not the character is the delimiter (comma or semicolon, for instance). If not, add it to the last element of the array you plan to return. If it is the delimiter, create a new empty string as the array's last element to start feeding your characters into.
I'm going to assume that this is homework, so I will only give snippets as hints:
Finding indices of all occurrences of a given substring
Here's an example of using indexOf with the fromIndex parameter to find all occurrences of a substring within a larger string:
String text = "012ab567ab0123ab";
// finding all occurrences forward: Method #1
for (int i = text.indexOf("ab"); i != -1; i = text.indexOf("ab", i+1)) {
System.out.println(i);
} // prints "3", "8", "14"
// finding all occurrences forward: Method #2
for (int i = -1; (i = text.indexOf("ab", i+1)) != -1; ) {
System.out.println(i);
} // prints "3", "8", "14"
String API links
int indexOf(String, int fromIndex)
Returns the index within this string of the first occurrence of the specified substring, starting at the specified index. If no such occurrence exists, -1 is returned.
Related questions
Searching for one string in another string
Extracting substrings at given indices out of a string
This snippet extracts substring at given indices out of a string and puts them into a List<String>:
String text = "0123456789abcdefghij";
List<String> parts = new ArrayList<String>();
parts.add(text.substring(0, 5));
parts.add(text.substring(3, 7));
parts.add(text.substring(9, 13));
parts.add(text.substring(18, 20));
System.out.println(parts); // prints "[01234, 3456, 9abc, ij]"
String[] partsArray = parts.toArray(new String[0]);
Some key ideas:
Effective Java 2nd Edition, Item 25: Prefer lists to arrays
Works especially nicely if you don't know how many parts there'll be in advance
String API links
String substring(int beginIndex, int endIndex)
Returns a new string that is a substring of this string. The substring begins at the specified beginIndex and extends to the character at index endIndex - 1.
Related questions
Fill array with List data
You do now that most of the java standard libraries are open source
In this case you can start here
Use String tokenizer to split strings in Java without split:
import java.util.StringTokenizer;
public class tt {
public static void main(String a[]){
String s = "012ab567ab0123ab";
String delims = "ab ";
StringTokenizer st = new StringTokenizer(s, delims);
System.out.println("No of Token = " + st.countTokens());
while (st.hasMoreTokens()) {
System.out.println(st.nextToken());
}
}
}
This is the right answer
import java.util.StringTokenizer;
public class tt {
public static void main(String a[]){
String s = "012ab567ab0123ab";
String delims = "ab ";
StringTokenizer st = new StringTokenizer(s, delims);
System.out.println("No of Token = " + st.countTokens());
while (st.hasMoreTokens())
{
System.out.println(st.nextToken());
}
}
}
/**
* My method split without javas split.
* Return array with words after mySplit from two texts;
* Uses trim.
*/
public class NoJavaSplit {
public static void main(String[] args) {
String text1 = "Some text for example ";
String text2 = " Second sentences ";
System.out.println(Arrays.toString(mySplit(text1, text2)));
}
private static String [] mySplit(String text1, String text2) {
text1 = text1.trim() + " " + text2.trim() + " ";
char n = ' ';
int massValue = 0;
for (int i = 0; i < text1.length(); i++) {
if (text1.charAt(i) == n) {
massValue++;
}
}
String[] splitArray = new String[massValue];
for (int i = 0; i < splitArray.length; ) {
for (int j = 0; j < text1.length(); j++) {
if (text1.charAt(j) == n) {
splitArray[i] = text1.substring(0, j);
text1 = text1.substring(j + 1, text1.length());
j = 0;
i++;
}
}
return splitArray;
}
return null;
}
}
you can try, the way i did `{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String str = sc.nextLine();
for(int i = 0; i <str.length();i++) {
if(str.charAt(i)==' ') { // whenever it found space it'll create separate words from string
System.out.println();
continue;
}
System.out.print(str.charAt(i));
}
sc.close();
}`
The logic is: go through the whole string starting from first character and whenever you find a space copy the last part to a new string.. not that hard?
The way to go is to define the function you need first. In this case, it would probably be:
String[] split(String s, String separator)
The return type doesn't have to be an array. It can also be a list:
List<String> split(String s, String separator)
The code would then be roughly as follows:
start at the beginning
find the next occurence of the delimiter
the substring between the end of the previous delimiter and the start of the current delimiter is added to the result
continue with step 2 until you have reached the end of the string
There are many fine points that you need to consider:
What happens if the string starts or ends with the delimiter?
What if multiple delimiters appear next to each other?
What should be the result of splitting the empty string? (1 empty field or 0 fields)
You can do it using Java standard libraries.
Say the delimiter is : and
String s = "Harry:Potter"
int a = s.find(delimiter);
and then add
s.substring(start, a)
to a new String array.
Keep doing this till your start < string length
Should be enough I guess.
public class MySplit {
public static String[] mySplit(String text,String delemeter){
java.util.List<String> parts = new java.util.ArrayList<String>();
text+=delemeter;
for (int i = text.indexOf(delemeter), j=0; i != -1;) {
parts.add(text.substring(j,i));
j=i+delemeter.length();
i = text.indexOf(delemeter,j);
}
return parts.toArray(new String[0]);
}
public static void main(String[] args) {
String str="012ab567ab0123ab";
String delemeter="ab";
String result[]=mySplit(str,delemeter);
for(String s:result)
System.out.println(s);
}
}
public class WithoutSpit_method {
public static void main(String arg[])
{
char[]str;
String s="Computer_software_developer_gautam";
String s1[];
for(int i=0;i<s.length()-1;)
{
int lengh=s.indexOf("_",i);
if(lengh==-1)
{
lengh=s.length();
}
System.out.print(" "+s.substring(i,lengh));
i=lengh+1;
}
}
}
Result: Computer software developer gautam
Here is my way of doing with Scanner;
import java.util.Scanner;
public class spilt {
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
System.out.print("Enter the String to be Spilted : ");
String st = input.nextLine();
Scanner str = new Scanner(st);
while (str.hasNext())
{
System.out.println(str.next());
}
}
}
Hope it Helps!!!!!
public class StringWitoutPre {
public static void main(String[] args) {
String str = "md taufique reja";
int len = str.length();
char ch[] = str.toCharArray();
String tmp = " ";
boolean flag = false;
for (int i = 0; i < str.length(); i++) {
if (ch[i] != ' ') {
tmp = tmp + ch[i];
flag = false;
} else {
flag = true;
}
if (flag || i == len - 1) {
System.out.println(tmp);
tmp = " ";
}
}
}
}
In Java8 we can use Pattern and get the things done in more easy way. Here is the code.
package com.company;
import java.util.regex.Pattern;
public class umeshtest {
public static void main(String a[]) {
String ss = "I'm Testing and testing the new feature";
Pattern.compile(" ").splitAsStream(ss).forEach(s -> System.out.println(s));
}
}
static void splitString(String s, int index) {
char[] firstPart = new char[index];
char[] secondPart = new char[s.length() - index];
int j = 0;
for (int i = 0; i < s.length(); i++) {
if (i < index) {
firstPart[i] = s.charAt(i);
} else {
secondPart[j] = s.charAt(i);
if (j < s.length()-index) {
j++;
}
}
}
System.out.println(firstPart);
System.out.println(secondPart);
}
import java.util.Scanner;
public class Split {
static Scanner in = new Scanner(System.in);
static void printArray(String[] array){
for (int i = 0; i < array.length; i++) {
if(i!=array.length-1)
System.out.print(array[i]+",");
else
System.out.println(array[i]);
}
}
static String delimeterTrim(String str){
char ch = str.charAt(str.length()-1);
if(ch=='.'||ch=='!'||ch==';'){
str = str.substring(0,str.length()-1);
}
return str;
}
private static String [] mySplit(String text, char reg, boolean delimiterTrim) {
if(delimiterTrim){
text = delimeterTrim(text);
}
text = text.trim() + " ";
int massValue = 0;
for (int i = 0; i < text.length(); i++) {
if (text.charAt(i) == reg) {
massValue++;
}
}
String[] splitArray = new String[massValue];
for (int i = 0; i < splitArray.length; ) {
for (int j = 0; j < text.length(); j++) {
if (text.charAt(j) == reg) {
splitArray[i] = text.substring(0, j);
text = text.substring(j + 1, text.length());
j = 0;
i++;
}
}
return splitArray;
}
return null;
}
public static void main(String[] args) {
System.out.println("Enter the sentence :");
String text = in.nextLine();
//System.out.println("Enter the regex character :");
//char regex = in.next().charAt(0);
System.out.println("Do you want to trim the delimeter ?");
String delch = in.next();
boolean ch = false;
if(delch.equalsIgnoreCase("yes")){
ch = true;
}
System.out.println("Output String array is : ");
printArray(mySplit(text,' ',ch));
}
}
Split a string without using split()
static String[] splitAString(String abc, char splitWith){
char[] ch=abc.toCharArray();
String temp="";
int j=0,length=0,size=0;
for(int i=0;i<abc.length();i++){
if(splitWith==abc.charAt(i)){
size++;
}
}
String[] arr=new String[size+1];
for(int i=0;i<ch.length;i++){
if(length>j){
j++;
temp="";
}
if(splitWith==ch[i]){
length++;
}else{
temp +=Character.toString(ch[i]);
}
arr[j]=temp;
}
return arr;
}
public static void main(String[] args) {
String[] arr=splitAString("abc-efg-ijk", '-');
for(int i=0;i<arr.length;i++){
System.out.println(arr[i]);
}
}
}
You cant split with out using split(). Your only other option is to get the strings char indexes and and get sub strings.