# C++ > Algorithms Code Examples

## A C++ Program to Multiply two Matrices. Divide And Conquer Algorithm

``` A C++ Program to Multiply two Matrices. Divide And Conquer Algorithm Code : # include <iostream.h> # include <stdlib.h> # include <conio.h> class Matrix { private: float matrix_a[3][3]; float matrix_b[3][3]; float matrix_c[3][3]; public: Matrix( ); void get_matrix_a( ); void get_matrix_b( ); void multiply_matrices( ); void show_result_Matrix( ); }; Matrix::Matrix( ) { for(int i=0;i<3;i++) { for(int j=0;j<3;j++) { matrix_a[i][j]=0; matrix_b[i][j]=0; matrix_c[i][j]=0; } } gotoxy(1,1); cout<<" ************************************************************************** ****"<<endl; cout<<" * * * * * * * * * * * * * * Matrix Multiplication * * * * * * * * * * * * *"<<endl; cout<<" ************************************************************************** ****"<<endl; gotoxy(1,25); cout<<" ************************************************************************** ****"; } void Matrix::get_matrix_a( ) { gotoxy(1,6); cout<<" Enter the values of the Matrix A row by row : "<<endl; cout<<" Ú ¿"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" À Ù"<<endl; gotoxy(18,10); cout<<" A = "<<endl; int x=28; int y=9; for(int i=0;i<3;i++) { for(int j=0;j<3;j++) { gotoxy(x,y); cin>>matrix_a[i][j]; x+=5; } x=28; y++; } } void Matrix::get_matrix_b( ) { gotoxy(1,15); cout<<" Enter the values of the Matrix B row by row : "<<endl; cout<<" Ú ¿"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" À Ù"<<endl; gotoxy(18,19); cout<<" B = "<<endl; int x=28; int y=18; for(int i=0;i<3;i++) { for(int j=0;j<3;j++) { gotoxy(x,y); cin>>matrix_b[i][j]; x+=5; } x=28; y++; } } void Matrix::multiply_matrices( ) { for(int i=0;i<3;i++) { for(int j=0;j<3;j++) { float value=0; float sum=0; for(int k=0;k<3;k++) { value=matrix_a[j][k]*matrix_b[k][j]; sum+=value; } matrix_c[i][j]=sum; } } } void Matrix::show_result_Matrix( ) { clrscr( ); gotoxy(1,1); cout<<" ************************************************************************** ****"<<endl; cout<<" * * * * * * * * * * * * * * Matrix Multiplication * * * * * * * * * * * * *"<<endl; cout<<" ************************************************************************** ****"<<endl; gotoxy(1,6); cout<<" The values of Matrix A and B are :"<<endl; cout<<" Ú ¿ Ú ¿"<<endl; cout<<" ³ ³ ³ ³"<<endl; cout<<" ³ ³ ³ ³"<<endl; cout<<" ³ ³ ³ ³"<<endl; cout<<" À Ù À Ù"<<endl; gotoxy(45,9); cout<<" B = "<<endl; gotoxy(10,9); cout<<" A = "<<endl; gotoxy(1,15); cout<<" The Product of Matrix A and B is : "<<endl; cout<<" Ú ¿"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" ³ ³"<<endl; cout<<" À Ù"<<endl; gotoxy(13,19); cout<<" A * B = "<<endl; int x_1=20; int y_1=8; int x_2=55; int y_2=8; int x_3=28; int y_3=18; for(int i=0;i<3;i++) { for(int j=0;j<3;j++) { gotoxy(x_1,y_1); cout<<matrix_a[i][j]; gotoxy(x_2,y_2); cout<<matrix_b[i][j]; gotoxy(x_3,y_3); cout<<matrix_c[i][j]; x_1+=5; x_2+=5; x_3+=5; } x_1=20; y_1++; x_2=55; y_2++; x_3=28; y_3++; } gotoxy(1,25); cout<<" ************************************************************************** ****"; } int main( ) { textmode(BW80); clrscr( ); Matrix Obj; Obj.get_matrix_a( ); Obj.get_matrix_b( ); Obj.multiply_matrices( ); Obj.show_result_Matrix( ); getch( ); return 0; } ```