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Creating a two dimensional string array [closed]

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For the question below use 2d array greetings seen below:
![image of 2D array][1]
"bob"
"joe"
"billy"
"george"
"janise"
"dell"
The code that I wrote is:
public class c
{
// instance variables - replace the example
below with your own
private int columns; int rows;
/**
* Constructor for objects of class c
*/
public c()
{
int columns = 2;
int rows = 3;
String[][] newArray = new String[columns][rows];
newArray[0][0] = "bob";
newArray[0][1] = "joe";
newArray[1][0] = "billy";
newArray[1][1] = "george";
newArray[1][2] = "janise";
newArray[2][2] = "dell";
for(int i = 0; i < rows; i++){
for(int j = 0; j < columns; j++){
System.out.println(newArray[i][j]);
}
}
}
}

When creating the array, you need to use new String[rows][columns], not new String[columns][rows].
The third row should then be assigned using newArray[2][0] and newArray[2][1].
You can use an array initializer to create the array in a much easier way:
String[][] newArray = { { "hello", "ni hao" },
{ "konnichiwa", "hola" },
{ "guten tag", "bonjour" } };

So... your code is close to being correct.
The first mistake is that you mixed the columns and rows: You are defining your array to have two columns, but in the end, you are using three (0, 1, 2).
The second mistake is in the last two assignments: You really did confuse the numbering here.
Your finished constructor should look like this:
int columns = 2;
int rows = 3;
String[][] newArray = new String[rows][columns];
newArray[0][0] = "hello";
newArray[0][1] = "ni hao";
newArray[1][0] = "konnichiwa";
newArray[1][1] = "hola";
newArray[2][0] = "guten tag";
newArray[2][1] = "bonjur";
for(int i = 0; i < rows; i++){
for(int j = 0; j < columns; j++){
System.out.println(newArray[i][j]);
}
}

iterate on sets of string in java [closed]

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i have program that makes operations on string and this is the principal function of one of those operations,this works perfectly,but it is not efficient:
private void printString(ArrayList<String> operations, ArrayList<String> set) {
int numerOfStrings = 0;
int numberOfletters = 0;
String toPrint = operations.get(1);
outOfLoop: for (int i = 0; i < set.size(); i++) {
String[] toFind = set.get(i).split(" ");
for (int k = 0; k < toFind.length; k++) {
if (toPrint.equals(toFind[k])) {
String[] splited = set.get(i).split(" ");
for (int j = 0; j < splited.length; j++) {
numberOfletters += splited[j].length();
}
numerOfStrings = splited.length;
break outOfLoop;
}
}
}
System.out.println(numerOfStrings + " " + numberOfletters);
}
explanation:
this function takes as parameter a an arrayList of operations, and an arraylist of set:
for the arraylist of operations i get always a specific position so,i don't iterate , it is always O(1)
for the arrayList of set i have to iterate,or rather, as I think of that to proceed:
so , for example, if have as operation print foo i have to do these steps:
first of all i have to find where foo is :
inside set i can have this situation:
position 1 : {car tree hotel}
...
position n : {foo lemon coffee}
when i find the string foo i have to print the number of strings inside that position and the number of letters of each string,so in this case i will print :
3(number of strings) 14(number of letters)
my program works,and also this function works, but it is a nasty solution,and not efficent,what do you think, how can I improve in efficiency in my program?
question inserted on code Review

try this version:
private void printString(ArrayList<String> operations, ArrayList<String> set) {
int numerOfStrings = 0;
int numberOfletters = 0;
String toPrint = operations.get(1);
for (String s : set) {
if (s.contains(toPrint)) {
String[] arr = s.split(" ");
numerOfStrings = arr.length;
numberOfletters = s.length() - (numerOfStrings - 1);
break;
}
}
System.out.println(numerOfStrings + " " + numberOfletters);
}
The 'worst' case here would be O(n2), because of for loop O(n) and contains O(n).
hope it helps.

Insertion sort array java [closed]

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So I have to write code for an insertion sort that will sort an array of random ints, the array is already set up and working okay and everything but my sort is not, heres what i have:
for(int i =1; i< numberSort.length-1;i++){
int temp = numberSort[i];
int j = i-1;
while((j >= 0) && (numberSort[j]>temp)){
numberSort[j+1] = numberSort[j];
j = j-1;
}
numberSort[j+1] = temp;
}
}
It seems to me that that should work, however it does not, it moves the numbers around from their original position but does not order them in ascending order. Thanks for any help you may be able to offer.

This code works for me:
public static void main(String[] args) {
int[] numberSort = {22,7,2, 5, 7, 1, 2, 9,33,55,12,1,0};
for (int i = 1; i < numberSort.length; i++) {
int temp = numberSort[i];
int j = i - 1;
while ((j >= 0) && (numberSort[j] > temp)) {
numberSort[j + 1] = numberSort[j];
j = j - 1;
}
numberSort[j + 1] = temp;
}
for (int i = 0; i < numberSort.length; i++) {
System.out.println(numberSort[i]);
}
}
Gives output:
0
1
1
2
2
5
7
7
9
12
22
33
55

Adding Elements in an array [closed]

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Closed 9 years ago.
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array[0] = 1;
array[1] = 2;
array[2] = 3;
array[3] = 4;
items_arr = 4;
System.out.println("The elements in the array are: ");
for (int x = 0; x < items_arr; x++)
System.out.println("Array[" + x + "]=" + array[x]);
System.out.print("\n");
Scanner insert = new Scanner(System.in);
System.out.print("Enter an Element to Insert: ");
int input = insert.nextInt();
for (s = 0; s < items_arr; s++)
if (array[s] == input)
break;
items_arr++;
for (s = 0; s < items_arr; s++)
System.out.println("Array[" + s + "]=" + array[s]);
break;
The output is. The elements are
Array [0]= 1
Array [1]= 2
Array [2]= 3
Array [3]= 4
Enter an element to Insert: 5
Array [0]= 1
Array [1]= 2
Array [2]= 3
Array [3]= 4
Array [4]= 0
when I insert 5 it posts 0
any suggestions please.. thanks!

To insert in to the array you shuould be doing follwoing operation
array[s]=input
Two notes here
Arrays are fixed length, and you should be checking the array length before inserting values in to that,other wise you will get ArrayIndexOBException. Safer to sue List/Set
As better coding practise, and to improve the readablity, you should be enclosing the conditional/loop statements (such as if or for) - see eg below
eg: 1
for (int x = 0;x<items_arr;x++) {
System.out.println("Array["+x+"]="+array[x]);
}
eg 2:
for(int s = 0; s < items_arr; s++) {
if (array[s] == input) {
break;
}
}

You have not inserted 5 in your array,
do something after items_arr++
array[ items_arr] = input;
If you do not insert any thing then by default every element is 0

You should be using a Collection type; I would recommend an ArrayList - that is -
List<Integer> al = new ArrayList<Integer>();
for (int i = 1; i < 5; i++) {
al.add(i);
}
Scanner insert = new Scanner(System.in);
System.out.print("Enter an Element to Insert: ");
int input = insert.nextInt();
al.add(input); // And so on...

You are not updating/inserting the array with the new input.
for(s = 0; s < items_arr; s++)
if (array[s] == input)
break;
items_arr++;
just replace the above code with
array[ items_arr] = input;
items_arr++;

how do I compare the string in a1 to the string in a2 to see which is bigger? [closed]

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Write a static method named joiner that accepts two arrays of strings a1 and a2 as parameters and returns a new array a3 such that each element of a3 at each index i stores a new string composed of the words stored at a1[i] and a2[i] joined together with the word with the work having greater length (more characters) at the front of the concatenated string. If there is a tie, take the element from a1.
For example, if a1 and a2 store the following elements:
String[] a1 = {"star", "pie", "jelly bean", "car"};
String[] a2 = {"cookie", "fig", "banana", "soda"};
Then your method should return the new array:
{"cookiestar", "piefig", "jelly beanbanana", "sodacar"}.
This is what i got so far:
for(int i = 0; i <length; i++) {
if(a1[i].stringlength()< a2[i].stringlength()) {
String[] a3 = a1[i] + a2[i];
}
else {
if(a2[i].stringlength().compareTo[i].stringlength() < 0) {
String[] a3 = a2[i] + a1[i];
}
else {
String[] a3 = a1[i] + a2[i];
}
return a3[i];
}
}
Alot of errors but i tried alot of different things and cant seem to figure it out
. I'm trying to figure out how to compare the strings in both arrays by the index. How would I compare a1[i] and a2[i] to see which string is bigger? And how would assign both strings to a new array a3?

The question does not specify if the two arrays of strings a1 and a2 are always the same length, and if not what to do when they are not, however with that in mind the following code works for when they are equal in length:
public static String[] joiner(String[] a1, String[] a2)
{
int length1 = a1.length;
int length2 = a2.length;
String[] a3 = new String[length1];
if( length1 == length2) {
for( int i = 0; i < length1; i++) {
if( a1[i].length() >= a2[i].length())
a3[i] = a1[i].concat(a2[i]);
else
a3[i] = a2[i].concat(a1[i]);
}
}
return a3;
}