Here we discuss a C++ program to subtract two matrices in a two-dimensional array.
The matrix can be defined as an array of arrays or multidimensional arrays in a table format like rows and columns where the data is stored. For example, mat[r][c]
Where,
The size or of the order of a matrix is defined as the number of rows and columns that the matrix has. A matrix with 'a' rows and 'b' columns is called an 'a × b' matrix.
We can do the matrix subtraction only when the order of both matrices matches. To subtract two matrices, we have to subtract the elements of the correct position of matrix A from the element of matrix B.
Here the user is asked to enter the number of rows r and the number of columns c. The value of r and c should be less than 100 here for this C++ program.
Read the elements into the first array from the user using a nested for loop and store the elements into the first matrix. Similarly read elements for the second matrix, b [i] [j].
Access each corresponding element from both arrays of 'a' and 'b' and subtract the elements and store it in the corresponding position of another array called sub [i] [j] . nested for loop is used for the subtraction of each element in the table formated matrix.
Sub[i][j] = a[i] [j] - B[i][j]. Display the matrix sub.
Step 1: Call the header file iostream.
Step 2: Use the namespace std
.
Step 3: Open the integer type main function; int main().
Step 4: Declare integer type variables r , c, I, j; and array a[100][100], b[100][100], sub[100][100];
Step 5: Ask the user to enter the number of rows ( 1 to 100 ).
Step 6: read the number into the variable r;
Step 7: Ask the user to enter the number of columns (1 to 10);
Step 8: read the number into the variable c;
Step 9: Ask the user to enter the elements of the 1st matrix.
Step 10: Read the elements into the array a[100][100];
Step 11: Ask the user to enter the elements of the 2nd matrix;
Step 12: Read the elements into the array b[100][100];
Step 13: Get the first elements of both matrix a[100][00] and b[100][100] and subtract the elements and store them in the first position of the matrix sub[100][100].
Step 14: Continue step 13 until a[r][c] and b[r][c] and store the result in sub[r][c];
Step 15: Display sub[100][100]
Step 16: exit.
#include <iostream>
using namespace std;
int main()
{
int r, c, a[100][100], b[100][100], sub[100][100], i, j;
cout << "Enter number of rows (between 1 and 100): ";
cin >> r;
cout << "Enter number of columns (between 1 and 100): ";
cin >> c;
cout << endl << "Enter elements of 1st matrix: " << endl;
// Storing elements of first matrix entered by user.
for(i = 0; i < r; ++i)
for(j = 0; j < c; ++j)
{
cout << "Enter element a" << i + 1 << j + 1 << " : ";
cin >> a[i][j];
}
// Storing elements of second matrix entered by user.
cout << endl << "Enter elements of 2nd matrix: " << endl;
for(i = 0; i < r; ++i)
for(j = 0; j < c; ++j)
{
cout << "Enter element b" << i + 1 << j + 1 << " : ";
cin >> b[i][j];
}
// Adding Two matrices
for(i = 0; i < r; ++i)
for(j = 0; j < c; ++j)
sub[i][j] = a[i][j] - b[i][j];
// Displaying the resultant sum matrix.
cout << endl << "Subtracted result of two matrix is: " << endl;
for(i = 0; i < r; ++i)
for(j = 0; j < c; ++j)
{
cout << sub[i][j] << " ";
if(j == c - 1)
cout << endl;
}
return 0;
}
Enter number of rows (between 1 and 100): 2 Enter number of columns (between 1 and 100): 2 Enter elements of 1st matrix: Enter element a11 : 6 Enter element a12 : 9 Enter element a21 : 8 Enter element a22 : 4 Enter elements of 2nd matrix: Enter element b11 : 8 Enter element b12 : 6 Enter element b21 : 2 Enter element b22 : 4 Subtracted result of two matrix is: -2 3 6 0