Write a function in C++ which accepts an integer array and its size as arguments / parameters and assign the elements into a two dimensional array of integers in the following format:

                                                                         CBSE 2006

If the array is 1 2 3 4 5 6

The resultant 2 D array is given below

1 2 3 4 5 6

1 2 3 4 5 0

1 2 3 4 0 0

1 2 3 0 0 0

1 2 0 0 0 0

1 0 0 0 0 0

If the array is 1 2 3

The resultant 2 D array is given below

1 2 3

1 2 0

1 0 0

#include<iostream.h>

#include<conio.h>

void form_matrix(int ar[], int m)

{

// forming the matrix 

int mat[m][m];

int max = m;

int min = 1;

for(int i = 0; i < m ; i++)

{

min= 1;

for(int j = 0; j < m ; j++, min++)

{

if(min < = max )

   mat[i][j] = min;

else

   mat[i][j] = 0;

}

max--;

}

cout<<" \n The matrix :";

// Displaying the matrix

for( i = 0 ; i < m; i++)

{

cout << "\n ";

for( j = 0 ; j< m ; j++)

cout << mat[i][j] << " ";

}

}

void main()

{

int m[10], sz, i, j;

cout<< " \n What is the size of an array ?";

cin >>  sz;

/* for inputing the  elements.....*/

for( i = 0 ; i < sz; i++)

m[i] = i+1;

cout << "\n The array ";

/* display array */

for( i = 0; i < sz ; i++)

cout<< m[i];

 /* call the function */

form_matrix(m, sz);

getch();

}

Write a function int ALTERSUM( int B[][5] , int N, int M) in c++ to find and return the sum of elements from all alternate elements of a two-dimensional array starting from B[0][0].

Hint: If the following is the content of the array

4 5 1

2 8 7

9 6 3

The function should add elements B[0][0], B[0][2], B[1][1], B[2][0], B[2][2]

CBSE 2010

#include<iostream.h>

#include<conio.h>

#define x 10

#define y 5

int ALTERSUM(int B[][5], int M, int N)

{

int flag = 0, sum = 0;

for(int i = 0 ; i < M ; i++)

for(int j = 0 ; j < N ; j++)

{

if(flag == 0)

{ 

   sum = sum + B[i][j];

   flag = 1;

}

else

   flag = 0;

}

return sum;

}

void main()

{

int arr[x][y], r, c, i , j;

cout << "\n How many rows(<10)? " ;

cin >> r;

cout << "\n How many cols(< 5)?";

cin >> c;

/* Input elements */

for( i = 0 ; i < r ; i++)

for(j = 0 ; j< c ; j++)

{

cout << "\n Enter elements :";

cin >> arr[i][j];

}

/* display matrix */

for(i = 0; i < r  ; i++)

for(j = 0; j < c ; j ++)

    cout << arr[i][j] << " ";

cout<< endl;

int sum = ALTERSUM(arr, r, c);

cout << "\n The Sum of alternate elements = " << sum;

getch();

}

Write a function in C++ to print the product of each column of a two dimensional integer array passed as the argument of the function.

                                                    CBSE 2008

Explain : If the two dimensional array contains

         1     2     4

         3     5     6

         4     3     2

         2     1     5

The output should appear as :

Product of Column 1 = 24

Product of Column 2 = 30

Product of Column 3 = 240

                                                                                             

#include<iostream.h>

#include<conio.h>

#define r 10

# define c 10

void ProCol(int a[][], int m , int n) 

// n represents column

// m represents row

{

int pro[n], i, j ;

for(i = 0; i  <  n ; i++)

{

pro[i] = 1;

for(j = 0 ; j  <  m ; j ++)

{

pro[i] = pro[i] * a[j][i];

}

cout << "\n Product of Column 1 : " <<  pro[i];

}

}

void main()

{

int arr[r][c];

int row, col, i, j;

// Input dimension ~

cout <<  "\n Enter row & Column :";

cin >>  row >>  col ;

// Input elements for the array ~

for( i = 0; i <  row ; i++)

for ( j = 0 ; j <  col ; j++)

{

cout << "\n Enter the element for position : "   << i+1 << " , " <<  j+1 ;

cin >>  arr[i][j];

}

// Display the array

for( i = 0;  i < row ; i++ )

{

for( j =0 ; j < col ; j ++)

    cout   <<  arr[i][j]   <<  "  ";

cout  <<   endl;

}

// Calling the function

ProCol(arr, row, col);

getch();

}

Define a function SWAPCOL() in C++ to swap (interchange) the first column elements with the last column elements, for a two dimensional integer array passed as the argument of the function.

Example : If the two dimensional array contains 

       2   1   4   9

       1   3   7   7 

       5   8   6   3

       7   2   1   2

After swapping of the content of 1st column and the last column, it should be :

      9   1   4   2

      7   3   7   1

      3   8   6   5

      2   2   1   7                                (CBSE 2009)

#include<iostream.h>

#include<conio.h>

void swapcol(int a[][], int r, int c)
   // r -> row, c ->col

{ int t;

for(int i = 0; i< r ; i++)

{

t = a[i][0];

a[i][0] = a[i][c-1];

a[i][c-1] = t;

}

}

void main()

{

int arr[10][10];

int m, n, i, j;

cout<<"\n Enter rows & columns :";

int m, n;

cin >> m >> n;

/* Input Array Elements */

for ( i = 0; i< m ; i++)

for( j = 0; j < n ; j++)

{

cout<< "\n Enter element for the array[ " << i+1 << " ] "<< " [ " << j+i << "]" ;

cin >> arr[i][j];

}

/* Swap function call */

swapcol(arr, m, n);

/* Display Array in Matrix form */

for( i = 0; i < m ; << i ++)

{ cout<< endl;

for (  j = 0; j < n ; j ++)

cout << arr[i][j] << "  ";

}

getch();

}

Write a C++ program to use the following function :

(i) display() to display a matrix of a size m x n.
(ii) times2() to double each number of the matrix of size mxn.
(iii) main() to read a matrix of size mxn and then to display original matrix and then to display the new matrix formed by doubling its elements.

#include<iostream.h>

#include<conio.h>

void display(int a[][], int m, int n)
{
for(int i = 0; i< m ; i++)
 {
  for( int j = 0; j< n ; j++)
        cout << a[i][j] << "  ";
   cout<< endl;
 }
}

void times2(int a[][], int m, int n)
{
for(int i = 0; i< m ; i++)

  for( int j = 0; j< n ; j++)
     a[i][j] = a[i][j] * 2;


}


void main()
{
int mat[10][10], row, col, i, j;

cout<< "\n Enter total rows :";
cin>> row;

cout<<" \n Enter total columns :";
cin>> col;

cout<< "\n Enter the elements for Matrix:";

for(i = 0; i< row; i++)

  for(j = 0; j< col; j++)
     cin>>mat[i][j];


cout<<"\n The Original Matrix :";
display(mat, row, col);


times2(mat, row, col);


cout<<"\n The New Matrix :";


display(mat, row, col);


getch();
}

Write a program to enter elements of any square matrix. Then create another matrix which will store the double of each element of the previous matrix. Then print all the elements of the second matrix in row and column format.

#include<iostream.h>

#include<conio.h>

void main()
{
int mat[10][10],  n;


cout<< "\n Enter dimension of the square matrix :";
cin>> n;


/*  .. Input Matrix ..*/
for(int i =0 ; i< n ; i++ )
for ( int j = 0 ; j< n ; j++)
{
cout<< "\n Enter an element for position " << i+1 << " , " <<  j+1 << ": " ;
cin >> mat[i][j];
}


for( i =0 ; i< n ; i++ )


for ( j = 0 ; j< n ; j++)
mat[i][j] = 2* mat[i][j];


cout<<"\n The original matrix :";
for( i =0 ; i< n ; i++ )
{
for( j =  0 ; j< n ; j++)
cout<< mat[i][j] << "  ";
cout << "\n";
}


cout<<"\n The Output Matrix : "
for(i =0 ; i< n ; i++ )


{for(j=0; j< n ; j++)
cout<< mat[i][j] << "  ";
cout<< "\n" ;
}


getch();
}