How To Count 1st Duplicates Value In Array By Using Java
Apr 12, 2015
I have taken array int[] a = {33,33,5,5,9,8,9,9};
In this array so many values are duplicates means 33 comes twice & 5 also comes twice & 9 comes three times. But I want to count the first value which is duplicate means 33 is first value which comes twice so answer would be 2.
I try:
public class FindFirstDuplicate {
public static void main(String[] args) {
int c=0;
int[] a = {33,33,5,5,9,8,9,9};
outerloop:
for(int i = 0; i < a.length; i++) {
I'm trying to count the number of elements in an ArrayList which also have duplicates. So for example, in an ArrayList of strings which contains cat, cat, dog, horse, zebra, zebra, the answer should be two.
If an element is found to be a duplicate, that element should then be exempt from the search so if that element is found again it should not increase the duplicate count.
Here is my code:
public int countDuplicates() { int duplicates = 0; // TODO: Write the code to get the number of duplicates in the list for (int i = 0; i < list.size()-1;i++) { boolean found = false;
[Code] ....
I know it's wrong because right now it's still increasing the duplicate count for elements that have already been detected as duplicates. How can I make it stop doing this?
I have an array with the following characters {'E', 'L','E','P','H','A','N','T','P','O'}
now, I need an array that will store the first array such that only the occurence occurs e.g {'E','L','P','H','A','N','T','O'} Notice that the characters 'E' and 'P' occur twice and as a result were not repeated the second time in the new array.
How would one go about this using the counting elements technique?
I tried this but not sure how to use the counting elements technique.
char [] arr = new char{'E', 'L','E','P','H','A','N','T','P','O'}; char[] bucket = new char[(arr[0] * arr.length)]; for (int i = 0; i < len; i++) bucket[arr[i]]++;
It's supposed to count all of the duplicates in an array and print out how many occurrences of the value starting at whatever index, or if there are no duplicates state that. Basically:
No duplicates with value 1 beyond Index 0
There are 3 more occurrences of value 2 starting at index 1
There are 2 more occurrences of value 2 starting at index 2....
This is what I've got so far:
Java Code:
public static void main(String[] args) { int[] arr = {1, 2, 2, 3, 4, 2, 4, 3, 0, 5, 3, 2}; for(int i = 0; i<arr.length; i++){ int count = 0; for(int j = i+1; j<arr.length; j++){ if((arr[j] == arr[i]) && (i!=j)){ count++; System.out.print("There are " + count + " more occurrences of "); System.out.println(arr[i] + " starting at index " + i); } } } } mh_sh_highlight_all('java');
I am stuck on this exercise and I don't know what exactly is wrong. I think it's something with the .remove and the for each loop, but I am not sure.
public class seven { public static void main(String[] args) { ArrayList<String> list = new ArrayList<String>(); list.add("aaa"); list.add("brr"); list.add("unni");
[Code] ....
This is what i get
Exception in thread "main" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(Unknown Source) at java.util.ArrayList$Itr.next(Unknown Source) at seven.removeDuplicates(seven.java:24) at seven.main(seven.java:18)
I need to call the method to remove duplicates form my array, but it won't let me call the method, or I'm doing it incorrectly which is probably it.
import java.util.*; public class C_6_15_EliminateDuplicates { public static void main(String[] args) { int[] numbers = new int[10]; Scanner input = new Scanner(System.in); System.out.println("Enter " + numbers.length + " numbers: "); for (int i = 0; i < numbers.length; i++)
(Count occurrence of numbers) Write a program that reads the integers between 1 and 100 and counts the occurrences of each. Assume the input ends with 0. Here is a sample run of the program:
Enter the integers between 1 and 100: 2 5 6 5 4 3 23 43 2 0 2 occurs 2 times 3 occurs 1 time 4 occurs 1 time 5 occurs 2 times 6 occurs 1 time 23 occurs 1 time 43 occurs 1 time
Note that if a number occurs more than one time, the plural word "times" is used in the output.
I am attempting to count the unique strings (a.k.a flowers) in the array along with a count of any duplicates. An example is embedded in my code below. I've only pasted the part of the program I am having trouble with. I can't figure out what I am doing incorrectly.
private void displayFlowers(String flowerPack[]) { // TODO: Display only the unique flowers along with a count of any duplicates /* * For example it should say
I'm trying to write a program that counts the number of times each number in an array occurs. In theory I understand how it work, you take the first element in the array, compare it again the rest of the array and any time it occurs in the array you increment a counter by 1. Then move onto the next element A[1] and so on...
This is what I've done so far :
public static void main(String[] args) { int[] array = {5,6,2,5,2,2,0,1,6}; int count = 0; for(int i = 0; i <array.length; i++) { int val = array[i]; for(int j = i+1; j<array.length; j++)
[Code] .....
I think I'm on the right track as it correctly prints out the frequency of the first 3 elements, but I'm definitely going wrong somewhere as it just doesn't do it right after that!
I am trying to count the number of occurrences of a string in an array list. I used the following code:
int count = Collections.frequency(strings, search);
strings is the name of the array list and search is the string that I am trying to count the number of occurrences of. My program compiles correctly, but when I enter the string to search for, I get the following error: "Exception in thread "main" java.lang.NullPointerException at java.util.Collections.frquency(Collections.java:37 18)
Why am I getting this error message and how do I fix it?
I have to write some code to take names from the user and then order them in alphabetical order and then print them out which i have managed to do. However, i can't get it to count the characters in the names that the user enters or count the amount of vowels in the names.
This is the code ive written:
import javax.swing.JOptionPane; import java.util.Arrays; String[] names = new String[9]; int i; names[0] = JOptionPane.showInputDialog("Please enter a name"); names[1] = JOptionPane.showInputDialog("Please enter a name");
I'm trying to generate random 100 numbers, from 0 to 9, in an array using Math.random, but it only outputs 0s which is very confusing to me. Also, I need to be able to count how many different integers there are like 0s, 1s, 2s... 8s, 9s.
Here's my code, I only got as far as the array then got stumped on the counting part.
import java.util.Arrays; public class countDigits { public static void main(String[] args) { //Create random generator and values int numbers = (int)(Math.random() * 10); int arrayCount = 1;
I have problems getting the right number of times for each number of the array. Here is my code:
public static void main(String[] args) { int[] a = { 3, 13, 5, 9, 13, 6, 9, 13, 2, 3 }; int num = 3; int count = numbers(a, num); for (int i = 0; i < a.length; i++) {
I have to write a program that takes an array of grades and calculate the average and then count the number of grades that are above average and also count the number of grades that are below average. This is what I have so far, it calculate the average and tells me how many are above average... where and how do I get to count how many are below average
public class arrays{ public static void main(String[] args) { final int grades = 5; double[] numbers = new double[grades]; double sum = 0;
The <Product> tags can run into hundreds or thousands. Quality can have values like Good, Bad, Damaged. Color can also have various values (Blue, Red ..)
ItemID can repeat or can be different. So I want group by ItemID->Color->Good count or BadCount and TotalCount as below.
I think using Hashmaps (Hashmap1 for ItemID, Hashmap2 for color, Hashmap3 for quality) may do the work. But I have to parse the xml number of ItemID's multiply-by number of colors multiply by various colors times for this.
Any better algorithm is there in performance perspective using Java.
I have to count the comparisons in the quick sort. I have done it by using a global variable. But I am stuck in doing it recursively.
This is my code.
import static java.time.Clock.system; import java.util.Arrays; public class test { /** * The swap method swaps the contents of two elements in an int array. * * @param The array containing the two elements. * @param a The subscript of the first element. * @param b The subscript of the second element. * */
Write a method compressDuplicates that accepts a stack of integers as a parameter and that replaces each sequence of duplicates with a pair of values: a count of the number of duplicates, followed by the actual duplicated number. For example, suppose a variable called s stores the following sequence of values:
This new stack indicates that the original had 5 occurrences of 2 at the bottom of the stack followed by 2 occurrences of -5 followed by 4 occurrences of 3, and so on. This process works best when there are many duplicates in a row. For example, if the stack instead had stored:
bottom [10, 20, 10, 20, 20, 10] top
Then the resulting stack after the call ends up being longer than the original:
bottom [1, 10, 1, 20, 1, 10, 2, 20, 1, 10] top
If the stack is empty, your method should not change it. You may use one queue as auxiliary storage to solve this problem. You may not use any other auxiliary data structures to solve this problem, although you can have as many simple variables as you like. You may not use recursion to solve this problem. For full credit your code must run in O(n) time where n is the number of elements of the original stack.
I wrote a code but still having a problem with it , am I allowed to use 3 while loops ?
public void compressDuplicates(Stack<Integer> s ){ Stack<Integer> backup= new Stack<Integer>(); int count = 1; while(!s.isEmpty()){ int temp = s.pop();
I'm struggling with that piece of code, my intention is to check for the object I want to add before adding it, so there won't be any duplicate on my list. I'm not sure how could I do that, since I'm working with objects.
Person is a class with few parameters such as id, name, and few others.
I guess I should search for a person with the same id, since that has be unique, but can't get it right.
private ArrayList<person> model= new ArrayList<>(); //... if (model.contains(person))throw new IllegalArgumentException("duplicate"); else model.addElement(person);
I have a HashSet, which I created to prevent duplicates upon output, but of course it's printing duplicates(or else I wouldn't be posting this). The order of my output does not matter, nor the input. The data type is String in the format (x + "," + z), where x and z are integers, creating a collection of coordinate sets. So to prevent the output of duplicates, I'm trying to get rid of the duplicates before they are added to the collection.
I've tried doing a '.equals()' string comparison but what happens is, since my string is added via one variable, it compares itself to itself and if itself equals itself it won't be added to the collection. I really need to keep this as a comparison of a single variable, because creating a key for each value would be sooo ridiculous for this volume of inputs.
So, with that being said, I would like to add one copy of the string, discard the duplicates, and do this thousands of times..
How to sort data from a .csv file. The file has a column that contains duplicate groups, and a column that has duplicate employee id's. I need to take the data and sort it into rows. The employee's id will be in the first column, then the groups the employees belong in will occupy the following columns. The groups and employees are dynamic.
groups| empId ----------------- Group A| a1234 | Group A| e3456 | Group A| w3452 | Group A| d3456 | Group A| j7689 | [Code] ....
I want to format the .csv as follows:
-------------------------- empId | group 1 | group 2 | -------------------------- a1234 | group A | group B | --------------------------- w3452 | group A | group B | ---------------------------
