Skip to main content

Your Questions my Answers

[I have started this new section in which I will answer your questions publicly. Therefore, if you are having any confusions or problems, you can e-mails me at one.arvind@gmail.com. Please note that… read more]

Problem: I want to sort each row of a matrix in ascending order, after which I need to display another matrix whose elements are the column indices of the elements of the original matrix with respect to the corresponding elements of the sorted matrix. Please give a program to do so. eg.

Original matrix={
                 {9,4,2},
                 {7,3,8}
                };
Sorted Matrix=  {
                 {2,4,9},
                 {3,7,8}
                };
Column Index=   {
                 {2,1,0},
                 {1,0,2}
                };

Dominic [*], Student, Nigeria

[* Last Name Deleted on Request]

Solution: Nice question Dominic, here is the solution. I will not discuss anything here as I have included enough comments in the program itself.

  // C++ program to sort a matrix
  // row-wise and then calculate
  // column index of the sorted matrix
  // w.r.t the original matrix
  #include<iostream.h>

  #define ROW 2
  #define COL 3

  void main(void)
  {
   int i,j,k,temp;

   // declare two-dimensional arrays
   int matrix[ROW][COL];
   int sorted_matrix[ROW][COL];
   int col_index[ROW][COL];

   // input data from the user
   for(i=0;i<ROW;i++)
     for(j=0;j<COL;j++)
       cin>>matrix[i][j];

   // copy the matrix to another
   // matrix on which sorting will be done
   // because we don't want to change the
   // original matrix
   for(i=0;i<ROW;i++)
     for(j=0;j<COL;j++)
       sorted_matrix[i][j]=matrix[i][j];

   // bubble sorting is done here
   // row-wise. the first loop is to
   // sekect the row
   for(i=0;i<ROW;i++)
     for(j=0;j<COL;j++)
       for(k=0;k<(COL-1);k++)
         if (sorted_matrix[i][k]>sorted_matrix[i][k+1])
         {
          temp=sorted_matrix[i][k];
          sorted_matrix[i][k]=sorted_matrix[i][k+1];
          sorted_matrix[i][k+1]=temp;
         }
   // sorting complete

   // calculate the column index and store
   // to another matrix
   for(i=0;i<ROW;i++)
     for(j=0;j<COL;j++)
       for(k=0;k<COL;k++)
       {
        if(matrix[i][j]==sorted_matrix[i][k])
        col_index[i][j]=k;
       }
   // column index calulated

   cout<<endl;

   // display the sorted matrix
   cout<<"\n\nSorted Array:\n";
   for(i=0;i<ROW;i++)
   {
    for(j=0;j<COL;j++)
    cout<<" "<<sorted_matrix[i][j];

    cout<<endl;
   }

   cout<<endl;

   // display the column index
   cout<<"\n\nColumn Index:\n";
   for(i=0;i<ROW;i++)
   {
    for(j=0;j<COL;j++)
    cout<<" "<<col_index[i][j];

    cout<<endl;
   }
  }

Hope this helps!

Good-Bye!

Related Articles:

Popular posts from this blog

The Best Way(s) to Comment out PHP/HTML Code

PHP supports various styles of comments. Please check the following example: <?php // Single line comment code (); # Single line Comment code2 (); /* Multi Line comment code(); The code inside doesn't run */ // /* This doesn NOT start a multi-line comment block /* Multi line comment block The following line still ends the multi-line comment block //*/ The " # " comment style, though, is rarely used. Do note, in the example, that anything (even a multi-block comment /* ) after a " // " or " # " is a comment, and /* */ around any single-line comment overrides it. This information will come in handy when we learn about some neat tricks next. Comment out PHP Code Blocks Check the following code <?php //* Toggle line if ( 1 ) {      // } else {   ...

How to Create an HTML Form Linked with MySQL Database in PHP

If you're looking for example code and detailed discussion on how to create an HTML form that stores data in a MySQL database using PHP then this post might be what you're looking for. I assume that you're familiar with basic HTML, CSS, PHP coding, and  MySQL. I am going to divide this small project into two parts: The HTML form itself that takes input from the user and the PHP script that saves it into the database A table that displays the user-added data that has been saved in the database. We'll be dealing with the first part in this tutorial. Again I'd like to break this problem into a few parts so that it's easier for you to understand and probably gives you an insight into how breaking up a problem into smaller chunks can help make things clearer in your mind. Let's think about it, there is an HTML form (that is HTML code), then there is the PHP code that deals with the user-input data, and the MySQL database itself. For this tutorial, we'll b...

Fix For Toshiba Satellite "RTC Battery is Low" Error (with Pictures)

RTC Battery is Low Error on a Toshiba Satellite laptop "RTC Battery is Low..." An error message flashing while you try to boot your laptop is enough to panic many people. But worry not! "RTC Battery" stands for Real-Time Clock battery which almost all laptops and PCs have on their motherboard to power the clock and sometimes to also keep the CMOS settings from getting erased while the system is switched off.  It is not uncommon for these batteries to last for years before requiring a replacement as the clock consumes very less power. And contrary to what some people tell you - they are not rechargeable or getting charged while your computer or laptop is running. In this article, we'll learn everything about RTC batteries and how to fix the error on your Toshiba Satellite laptop. What is an RTC Battery? RTC or CMOS batteries are small coin-shaped lithium batteries with a 3-volts output. Most laptops use ...