Question

Java programming: I need to create a method that is given a 2D char array and a String that returns a part of the original 2D array. The input string will tell the method which rows from the input array need to be returned. For example, a 5x5 char array input along with a string "0 4" would return rows 1 and 5 of the input array. The String input will always be numbers divided by spaces and will not include numbers smaller than 0 nor numbers larger than inputArray.length-1 (because arrays count from 0 but .length counts from 1). The string input will also always be whole numbers. The output must be stored as a deep copy.  Return null when any of the parameters are empty or null

Example:

char[][] Input = {{'a', 'A', 'a', 'A', 'a'}, {'B', 'b', 'B', 'b', 'B'}, {'c', 'C', 'c', 'C', 'c'}, {'D', 'd', 'D', 'd', 'D'}}

String Input = "3 0 1"

char[][] Output = {{'D', 'd', 'D', 'd', 'D'}, {'a', 'A', 'a', 'A', 'a'}, {'B', 'b', 'B', 'b', 'B'}} (must be deep copy, not printed in the command window)

Answer 1

The answer to this question is as follows:

The code is as follows:

import java.util.*;
public class MyClass {
public static void main(String args[]) {
int rows,columns;
String str;
Scanner sc=new Scanner(System.in);
//reading the string
str=sc.nextLine();
char[][] input=new char[10][20];
char[][] output=new char[10][20];
//reading the rows and columns for the dimensions of the array
rows=sc.nextInt();
columns=sc.nextInt();
//reading the values into the input array is as follows
for(int i=0;i<rows;i++)
{
for(int j=0;j<columns;j++)
{
input[i][j]=sc.next().charAt(0);
}
}
//spliting the string and stroing the values into the ouput array
String[] array=str.split(" ");
int length=array.length;
for (String a : array)
{
int temp = Integer.parseInt(a);
for(int i=temp;i<length;i++)
{
for(int j=0;j<columns;j++)
{
output[i][j]=input[i][j];
}
}
}
//displaying the values that are stored in the output array
for(int i=0;i<length;i++)
{
for(int j=0;j<columns;j++)
{
System.out.print(output[i][j]+",");
}
System.out.println();
}

  
}
}

The input and ouput is as follows:

The example input is as follows:

3 0 1
4 5
a A a A a B b B b B c C c C c D d D d D

Here 3 0 1 represents the string

and the 4 5 represents the rows and columns for the dimensions for the array

and the last line is for the character array