Create file file1 with the following values 3 4 35 20 43 17

Create file, file1, with the following values: 3 4 35 20 -43 17 10 6 7 -2 13 1 2 3 Write a program in Java to do the following: Open \"file1\" and read the first two values, r and c, which are supposed to indicate the dimensions of the two-dimensional array whose values are given in the file after the values of r and c. Create a two-dimensional array of size r times c Populate the two-dimensional array created in the previous step by reading values from file1. Create another two-dimensional array of size c times r Write a function, rcConvert. using multiple for loops to convert r times c to c times r such that c times r. appears as follows: 35 -10 13 20 6 6 1 -43 7 2 17 -2 3 Write a function, storelnFile, to store c times r array in file file2. Call functions rcConvert and storelnFile from the main program to convert r times c to c times r and store the converted array in file2. Use structures like functions, while, do while, switch, fo and if where needed.

Solution

Please follow the code and comments for description :

CODE :

// required imports for the code to run
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Arrays;

// class to run the code
public class Transpose
{
// driver method
public static void main(String[] args)
{
// required readers and writers
BufferedReader br = null;
FileReader fr = null;
BufferedWriter bw = null;
FileWriter fw = null;
try
{
// code to read the data
System.out.println(\"Reading the Data...\");
fr = new FileReader(\"file1.txt\");
br = new BufferedReader(fr);
  
// local variables
int lineCount = 0, r = 0, c = 0, i = 0;
int arr[][] = null;
int arr1[][] = null;
String sCurrentLine;
  
// read the data till the EOF
while ((sCurrentLine = br.readLine()) != null)
{
lineCount++;
String tokens[] = sCurrentLine.split(\" \");
  
// based on the rows and columns create and assign the data
if (lineCount == 1)
{
int[] array = Arrays.stream(tokens).mapToInt(Integer::parseInt).toArray();
r = array[0];
c = array[1];
arr = new int[r][c];
} else
{
for (int j = 0; j < c; j++)
{
arr[i][j] = Integer.parseInt(tokens[j]); // parse the data
}
i++; // increment the count
}
}
  
// method call to get the data transposed
arr1 = rcConvert(arr, r, c);

// file write objects
System.out.println(\"Writing the data...\");
fw = new FileWriter(\"file2.txt\");
bw = new BufferedWriter(fw);
for (int x = 0; x < c; x++)
{
for (int y = 0; y < r; y++)
{
bw.write(arr1[x][y] + \"\\t\"); // write the data
}
bw.write(\"\ \");
}
// end data message
System.out.println(\"Done\");
} catch (IOException e) // catch the exceptions if any
{
e.printStackTrace();
} finally
{
try
{
// close all the instances
if (br != null)
{
br.close();
}
if (fr != null)
{
fr.close();
}

if (bw != null)
{
bw.close();
}
if (fw != null)
{
fw.close();
}
} catch (IOException ex)
{
ex.printStackTrace();
}
}
}

// method that transposes the matrix and returns the data
private static int[][] rcConvert(int array[][], int rows, int columns)
{
int trArr[][] = new int[columns][rows];
for (int c = 0; c < rows; c++)
{
for (int d = 0; d < columns; d++)
{
trArr[d][c] = array[c][d];
}
}
return trArr;
}
}

OUTPUT :

Reading the Data...
Writing the data...
Done

file1.txt :

3 4
35 20 -43 17
-10 6 7 -2
13 1 2 3

file2.txt :

35   -10   13  
20   6   1  
-43   7   2  
17   -2   3  

Hope this is helpful.