I'm writing a program that has two rules:
1. If the first character of the word is a vowel, then move it to the end of the word.
2. If the first character of the word is a consonant, then move it to the end of the word and append 'ae'.
import java.util.Scanner;
public class Program5 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner scanner = new Scanner(System.in);
System.out.print("Please enter a sentence: ");
String english = scanner.nextLine();
String piggy = piggyEnglish(english);
System.out.print("Translated: " + piggy);
}
private static String piggyEnglish(String s) {
String piggy = "";
int i = 0;
while (i<s.length()) {
while (i<s.length() && !isLetter(s.charAt(i))) {
piggy = piggy + s.charAt(i);
i++;
}
if (i>=s.length()) break;
int begin = i;
while (i<s.length() && isLetter(s.charAt(i))) {
i++;
}
int end = i;
piggy = piggy + piggyWord(s.substring(begin, end));
}
return piggy;
}
private static boolean beginsWithVowel(String word){
String vowels = "aeiou";
char letter = word.charAt(0);
return (vowels.indexOf(letter) != -1);
}
private static boolean isLetter(char c) {
return ( (c >='A' && c <='Z') || (c >='a' && c <='z') );
}
private static String piggyWord(String word) {
int split = firstVowel(word);
if(beginsWithVowel(word)) {
return word.substring(split) + word.substring(0, split);
} else {
return word.substring(split) + word.substring(0, split)+"ae";
}
}
private static int firstVowel(String word) {
word = word.toLowerCase();
for (int i=0; i<word.length(); i++)
if (word.charAt(i)=='a' || word.charAt(i)=='e' ||
word.charAt(i)=='i' || word.charAt(i)=='o' ||
word.charAt(i)=='u')
return i;
return 0;
}
}
The following is the expected output:
Please enter a sentence: today is a beautiful day
Translated: odaytae si a eautifulbae aydae
However, this is what I'm getting:
Please enter a sentence: today is a beautiful day
Translated: odaytae is a eautifulbae aydae
Basically, it doesn't translate any words that start with a vowel. I think the problem stems from the piggyWord method, but I'm not certain. Can I get any pointers on how to fix this?
The error lies in the piggyWord function:
private static String piggyWord(String word) {
int split = firstVowel(word);
if(beginsWithVowel(word)) {
return word.substring(split + 1) + word.substring(0, split + 1); //Since vowel is in 1st place, substring(0,0) returns empty string.
} else {
return word.substring(split) + word.substring(0, split)+"ae";
}
}
Based on your rules, you don't need the method firstVowel() to get the index of the first vow in a word because you only need to know whether the first character in the word is a vow or not.
So simply change you piggyWord method to the following will solve your problem:
private static String piggyWord(String word) {
if(beginsWithVowel(word)) {
return word.substring(1) + word.substring(0, 1);
} else {
return word.substring(1) + word.substring(0, 1)+"ae";
}
}
Or more simply:
private static String piggyWord(String word) {
String result = word.substring(1) + word.substring(0, 1);
return beginsWithVowel(word) ? result : result + "ae";
}
Because you always have to move the first character of a word to the end, the only thing is that whether you need to append an extra "ae" in the end or not.
If only the first letter is concerned than in "firstVowel" you can return 1 if vowel is at first position.
private static int firstVowel(String word) {
word = word.toLowerCase();
for (int i=0; i<word.length(); i++)
if (word.charAt(i)=='a' || word.charAt(i)=='e' ||
word.charAt(i)=='i' || word.charAt(i)=='o' ||
word.charAt(i)=='u')
return 1;
return 0;
}
Related
I'm making a Palindrome Generator. Basically the user inputs a word or sentence and the program outputs whether or not its a Palindrome, which is a word that is spelled the same forwards and backwards like "wow" or "racecar". My program works fine, however the output text will repeat itself like fifty times and I can't seem to figure out where the issue is without messing everything up. Help would be appreciated.
import javax.swing.JOptionPane;
public class palindromedectector {
public static void main(String[] args) {
String testStrings = "";
testStrings = JOptionPane.showInputDialog("Enter word: ");
for (int i = 0; i < testStrings.length(); i++)
{
System.out.print("\"" + testStrings + "\"");
if (isPalindrome(stripString(testStrings)))
System.out.println(" is a palindrome.");
else
System.out.println(" is not a palindrome.");
}
}
public static String stripString(String strip)
{
strip = strip.toUpperCase();
String stripped= "";
for (int i= 0; i< strip.length(); i++)
{
if (Character.isLetter(strip.charAt(i)))
stripped += strip.charAt(i);
}
return stripped;
}
public static boolean isPalindrome (String str)
{
boolean status = false;
if (str.length() <= 1)
status = true;
else if (str.charAt(0) == str.charAt(str.length()-1))
{
status = isPalindrome (str.substring(1, str.length()-1));
}
return status;
}
}
Main issue is that you run isPalindrome check for the same string in the loop, probably you wanted to run multiple checks
public static void main(String[] args) {
final int attempts = 5;
for (int i = 0; i < attempts; i++) {
String word = JOptionPane.showInputDialog("Enter word: ");
System.out.print("\"" + word + "\"");
if (isPalindrome(stripString(word))) {
System.out.println(" is a palindrome.");
} else {
System.out.println(" is not a palindrome.");
}
}
}
Also, the main functionality may be implemented in a shorter way:
// use regexp to get rid of non-letters
private static String stripString(String word) {
if (null == word || word.isEmpty()) {
return word;
}
return word.replaceAll("[^A-Za-z]", "").toUpperCase(); // remove all non-letters
}
// use Java Stream API to check letters using half of word length
private static boolean isPalindrome(String word) {
if (null == word) {
return false;
}
final int len = word.length();
if (len < 2) {
return true;
}
return IntStream.range(0, len/2)
.allMatch(i -> word.charAt(i) == word.charAt(len - 1 - i));
}
Basic problem: You are testing if the word is a palindrome testStrings.length() times, ie once for every letter in the word, rather than just once.
Remove the for loop in your main() method.
In this program, I am trying to return a new string that is composed of new letters that were added and old letters if the didn't fit the constraints. I am stuck in terms of I don't know how to fix my code so that it prints correctly. Any help or suggestions is greatly appreciated!
Here are some examples:
str: "asdfdsdfjsdf", word: "sdf", c: "q"
should return "aqdqjq", I'm getting "asdqqq"
str: "aaaaaaaa", word: "aaa", c: "w"
should return "wwaa", as of right now my code only returns "ww"
public static String replaceWordWithLetter(String str, String word, String c)
String result = "";
int index = 0;
while (index < str.length() )
{
String x = str.substring(index, index + word.length() );
if (x.equals(word))
{
x = c;
index = index + word.length();
}
result = result + x;
index++;
}
if (str.length() > index)
{
result = result + str.substring(index, str.length() - index);
}
return result;
}
You seem to be overcomplicating this. You can simply use the replace() method:
public static String replaceWordWithLetter(String str, String word, String c) {
return str.replace(word, c);
}
Which when called as:
replaceWordWithLetter("asdfdsdfjsdf", "sdf", "q")
Produces the output:
aqdqjq
The problem with your current method is that if the substring is not equal to word, then you will append as many characters as there are in word, and then only move up one index. If you will not be replacing the sequence, then you only need to append one character to result. Also it is much more efficient to use a StringBuilder. Also as noted if the String is not divisible by word.length(), this will throw a StringIndexOutOfBoundsError. To solve this you can use the Math.min() method to ensure that the substring does not go out of bounds. Original method with fixes:
public static String replaceWordWithLetter(String str, String word, String c) {
StringBuilder result = new StringBuilder();
int index = 0;
while (index < str.length() )
{
String x = str.substring(index, Math.min(index + word.length(), str.length()));
if (x.equals(word))
{
result.append(c);
index = index + word.length();
}
//If we aren't replacing, only add one char
else {
result.append(x.charAt(0));
index++;
}
}
if (str.length() > index)
{
result.append(str.substring(index, str.length() - index));
}
return result.toString();
}
Found the fix to my issue using #GBlodgett's code:
String result = "";
int index = 0;
while (index <= str.length() - word.length() )
{
String x = str.substring(index, index + word.length() );
if (x.equals(word))
{
result = result + c;
index = index + word.length();
}
else {
result = result + x.charAt(0);
index++;
}
}
if (str.length() < index + word.length())
{
result = result + (str.substring(index));
}
return result;
}
You can use String.replaceAll() method.
example:
public class StringReplace {
public static void main(String[] args) {
String str = "aaaaaaaa";
String fnd = "aaa";
String rep = "w";
System.out.println(str.replaceAll(fnd, rep));
System.out.println("asdfdsdfjsdf".replaceAll("sdf", "q"));
}
}
Output:
wwaa
aqdqjq
I'm trying to convert a sentence to pig latin but can't seem to get the correct output to work. For example the input
the rain in spain stays mainly in the plain yields an output of ethay ethay ethay with my current code whereas the expected output is ethay ainray inay ainspay aysstay ainlymay inay ethay ainplay
For those unfamiliar, the basic rules of pig latin are:
If the word begins with a consonant, take the beginning consonants up until the first vowel and move them to the end of the word. Then append ay at the very end. (so cricket would become icketcray)
If the word begins with a vowel, simply add ay to the end. (apple would become appleay)
If y is the first letter in the word, treat it as a consonant, otherwise it is used as a vowel. (young would become oungyay and system would become ystemsay)
My code is as follows:
import java.util.Scanner;
public class PigLatin{
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String line = scan.next();
String piglatin = translateSentence(line);
System.out.println(piglatin);
}
public static String translateSentence(String line){
for (int i =0; i < line.length(); i++ ) {
char c = line.charAt(i);
//for loop to analyze each word
if (Character.isAlphabetic(c)) {
//if (i <='a' || i<='A' || i>='z' || i>='Z'){
String piglatin = translateword(line);
return piglatin;
}
}
return line;
}
public static String translateword(String line) {
Scanner scan = new Scanner(System.in);
int position = firstVowel(line);
String words = "";
String output = "";
for(int i = 0; i<line.length();i++){
words = "";
if (firstVowel(line) == 0) {
words = line + "-way";
} else if (firstVowel(line) == -1) {
words = line + "";
} else {
String first = line.substring(position);
String second = line.substring(0,position) + "ay";
words = first + second;
}
output = output + " " + words;
//words = "";
}
return output;
}
public static int firstVowel(String line) {
for (int i = 0; i < line.length(); i++) {
if (line.charAt(i) == 'a' || line.charAt(i) == 'e'
|| line.charAt(i) == 'i' || line.charAt(i) == 'o'
|| line.charAt(i) == 'u') {
return i;
}
}
return -1;
}
}
Any help is greatly appreciated, thank you.
first write a separate function to get list of words from line
public String[] getWords(String line) {
String list[]=new String[100];
int j=0;
int end;
end=line.indexOf(' ');
while (end!=-1) {
list[j]=line.substring(0, end);
line=line.substring(end+1,line.length());
j++;
end=line.indexOf(' ');
}
list[j]=line.substring(0,line.length());
return list;
}
then modify your translate line to call translate word multiple times, each time pass a single word.
Assuming your translateWord() returns a single correctly translated word. translateLine change in the following way:
if (Character.isAlphabetic(c)) {
String wordList[]=getWords(line);
String piglatin="";
int i=0;
while(!line[i].equals("")) {
piglatin = piglatin+translateword(word[i]);
i++;
}
return piglatin;
}
we will say that two words are "charecter equale" if both of them has the same charecter, for example: baac and abac are charecter equale, I am trying to write a recursive function that gets a string s, a word w and integer k, that checks if there are exactliy k words in the string that they charecter equale to the word, for example: the function should return true for the word abac , the string aabc abdca caba xyz ab and the number k=2.
Ineed help at the recursive part, i.e the function searchMixed, my idea was first the check if the string contain only on word (base case),
the general case is to call the function searchMixed without the first word
public class recursion1 {
public static void main(String[] args) {
boolean result=searchMixed("abac","aabc abdca caba xyz ab",2);
System.out.println("result: "+result);
}
public static boolean searchMixed(String word, String s, int k)
{
if(s.indexOf(' ')==-1 && isEquale(word,s) && k==1)
return true;
if(s.indexOf(' ')==-1 && !isEquale(word,s) && k==1)
return false;
int pos=s.indexOf(' ');
System.out.println("index of"+ s.indexOf(' '));
String first_word=first_word=s.substring(0,pos);
if(isEquale(word, first_word))
searchMixed(word, s.substring(pos+1), k-1);
else
searchMixed(word, s.substring(pos+1), k);
return false;
}
.
//this function works fine, the function checks if two words are charecter equale
public static boolean isEquale(String word, String sub_string)
{
if(word.length()!=sub_string.length())
return false;
char[] s33=new char[sub_string.length()];
char[] sww=new char[word.length()];
for(int i=0;i<sub_string.length();i++)
s33[i]=sub_string.charAt(i);
for(int i=0;i<word.length();i++)
sww[i]=word.charAt(i);
for(int i=0;i<word.length();i++)
{
for(int j=0;j<sub_string.length();j++)
{
if(sww[i]==s33[j])
s33[j]='#';
}
}
for(int i=0;i<sub_string.length();i++)
if(s33[i]!='#')
return false;
return true;
}
}
YourString = YourString.replaceAll("\\s+", " ");
String[] words = YourString.split(" ");
... to split the words.
static int n = 0;
static String keyword = "aabc";
static String[] words = null;
public static void main()
{
n = 0;
// Let's assume you accept 'k' here.
String YourString = "aabc baca hjfg gabac";
words = YourString.split(" ");
rec(words[0]);
if (k <= n)
System.out.println(true);
else
System.out.println(false);
}
static int pos = 0;
public static void rec(String word)
{
boolean flag = true;
word += " ";
if(word.length() != keyword.length() + 1)
{
flag = false;
}
for(int i = 0; i < keyword.length() && flag; i++)
{
for(int j = 0; j < word.length(); j++)
{
if(word.charAt(j) == keyword.charAt(i))
{
word = word.substring(0, j) + word.substring(j+1);
break;
}
}
if(word.equals(" "))
{
n++;
break;
}
}
if(pos + 1 != words.length)
{
rec(words[++pos]);
}
}
Now, let me explain:
In the recursive method rec(String word), a space is added to it at the end of the word being checked (so that substring(j+1) does not go out of bounds)
If the keyword and the checked word are of different lengths, it stops checking, and moves on to '5'.
If the two words are of same lengths, the loop removes a single similar character from the word (That's what word = word.substring(0, j) + word.substring(j+1); does).
At the end of the loop, if all that is remaining of the word is a space, then the counter n increases by 1 and the loop exits.
If there is more than or equal to one more Strings in the array, position of the word being checked in the array increases by 1, and the next word in the array is passed to the rec(String word) method.
I am trying to reverse every 2nd words of every single sentence like
If a given string is :
My name is xyz
The desired output should be :
My eman is zyx
My current output is:
Ym eman s1 zyx
I am not able to achieve my desired output.Don't know what I am doing wrong here
Here is my code
char[] sentence = " Hi my name is person!".toCharArray();
System.out.println(ReverseSentence(sentence));
}
private static char[] ReverseSentence(char[] sentence)
{
//Given: "Hi my name is person!"
//produce: "iH ym eman si !nosrep"
if(sentence == null) return null;
if(sentence.length == 1) return sentence;
int startPosition=0;
int counter = 0;
int sentenceLength = sentence.length-1;
//Solution handles any amount of spaces before, between words etc...
while(counter <= sentenceLength)
{
if(sentence[counter] == ' ' && startPosition != -1 || sentenceLength == counter) //Have passed over a word so upon encountering a space or end of string reverse word
{
//swap from startPos to counter - 1
//set start position to -1 and increment counter
int begin = startPosition;
int end;
if(sentenceLength == counter)
{
end = counter;
}
else
end = counter -1;
char tmp;
//Reverse characters
while(end >= begin){
tmp = sentence[begin];
sentence[begin] = sentence[end];
sentence[end] = tmp;
end--; begin++;
}
startPosition = -1; //flag used to indicate we have no encountered a character of a string
}
else if(sentence[counter] !=' ' && startPosition == -1) //first time you encounter a letter in a word set the start position
{
startPosition = counter;
}
counter++;
}
return sentence;
}
If you want to reverse the alternate word you can try something like splitting the whole String into words delimited by whitespaces and apply StringBuilder reverse() on every second word like :-
String s = "My name is xyz";
String[] wordsArr = s.split(" "); // broke string into array delimited by " " whitespace
StringBuilder sb = new StringBuilder();
for(int i = 0 ; i< wordsArr.length; i++){ // loop over array length
if(i%2 == 0) // if 1st word, 3rd word, 5th word..and so on words
sb.append(wordsArr[i]); // add the word as it is
else sb.append(new StringBuilder(wordsArr[i]).reverse()); // else use StringBuilder revrese() to reverse it
sb.append(" ");// add a whitespace in between words
}
System.out.println(sb.toString().trim()); //remove extra whitespace from the end and convert StringBuilder to String
Output :- My eman is zyx
You can solve your problem vary easy way! Just use a flag variable which will indicate the even or odd position, more precisely whether any word will gonna be reversed or not!
Look at the following modification I made in your code, just added three extra line:
private static boolean flag = true;// added a variable flag to check if we reverse the word or not.
private static char[] ReverseSentence(char[] sentence)
{
//Given: "Hi my name is person!"
//produce: "iH ym eman si !nosrep"
if(sentence == null) return null;
if(sentence.length == 1) return sentence;
int startPosition=0;
int counter = 0;
int sentenceLength = sentence.length-1;
//Solution handles any amount of spaces before, between words etc...
while(counter <= sentenceLength)
{
if(sentence[counter] == ' ' && startPosition != -1 || sentenceLength == counter) //Have passed over a word so upon encountering a space or end of string reverse word
{
flag = !flag; // first time (odd position) we are not going to reverse!
//swap from startPos to counter - 1
//set start position to -1 and increment counter
int begin = startPosition;
int end;
if(sentenceLength == counter)
{
end = counter;
}
else
end = counter -1;
char tmp;
//Reverse characters
while(end >= begin & flag){ //lets see whether we are going to reverse or not
tmp = sentence[begin];
sentence[begin] = sentence[end];
sentence[end] = tmp;
end--; begin++;
}
startPosition = -1; //flag used to indicate we have no encountered a character of a string
}
else if(sentence[counter] !=' ' && startPosition == -1) //first time you encounter a letter in a word set the start position
{
startPosition = counter;
}
counter++;
}
return sentence;
}
Input
My name is xyz
Output:
My eman is zyx
The following code does this "special reverse" which reverses any other word in the sentence:
public static void main(String[] args) {
String sentence = "My name is xyz";
System.out.println(specialReverse(sentence)); // My eman is zyx
}
private static String specialReverse(String sentence) {
String result = "";
String[] words = sentence.split(" ");
// we'll reverse only every second word according to even/odd index
for (int i = 0; i < words.length; i++) {
if (i % 2 == 1) {
result += " " + reverse(words[i]);
} else {
result += " " + words[i];
}
}
return result;
}
// easiest way to reverse a string in Java in a "one-liner"
private static String reverse(String word) {
return new StringBuilder(word).reverse().toString();
}
Just for completeness here's Java-8 solution:
public static String reverseSentence(String input) {
String[] words = input.split(" ");
return IntStream.range(0, words.length)
.mapToObj( i -> i % 2 == 0 ? words[i] :
new StringBuilder(words[i]).reverse().toString())
.collect(Collectors.joining(" "));
}
reverseSentence("My name is xyz"); // -> My eman is zyx
package com.eg.str;
// Without using StringBuilder
// INPUT: "Java is very cool prog lang"
// OUTPUT: Java si very looc prog gnal
public class StrRev {
public void reverse(String str) {
String[] tokens = str.split(" ");
String result = "";
String k = "";
for(int i=0; i<tokens.length; i++) {
if(i%2 == 0)
System.out.print(" " + tokens[i] + " ");
else
result = tokens[i];
for (int j = result.length()-1; j >= 0; j--) {
k = "" + result.charAt(j);
System.out.print(k);
}
result = "";
}
}
public static void main(String[] args) {
StrRev obj = new StrRev();
obj.reverse("Java is very cool prog lang");
}
}
//reverse second word of sentence in java
public class ReverseSecondWord {
public static void main(String[] args) {
String s="hello how are you?";
String str[]=s.split(" ");
String rev="";
for(int i=0;i<str[1].length();i++)
{
char ch=str[1].charAt(i);
rev=ch+rev;
}
str[1]=rev;
for(int i=0;i<str.length;i++)
{
System.out.print(str[i]+" ");
}
}
}