Question

Write a function called multiply that takes two square matrices of the same size as arguments and returns their element-wise product. The type of the
matrices should be integers. Your code needs to handle matrices with multiple rows and columns, and calculate their product as: p[i][j]= a[i][j] * b[i][j]
where p is the product to return, a and b are the input argument matrices,
and i, j are index variables for the matrices. Print the return matrix in main

Answer 1

#include <iostream>
using namespace std;
#include <cstdlib>

void fn(int **arr) {

}
void fn2 (int **arr2){

}
void fn3 (int **arr3){

}
int main() {

int r, c ,r2 , c2 , r3 , c3 , m , l;

cout << "Enter size of row 1 : " ;
cin >> r ;
cout << "Enter size of column 1 : " ;
cin >> c ;
cout <<"Enter matrix 1 please " ;

int **arr = new int*[r];
for (int i = 0; i < r; i++)
arr[i] = new int[c];

for (int i=0 ; i<r ; i++){
for (int j=0 ; j<c ; j++)
cin >> arr[i][j] ;
}
for (int i=0 ; i<r ; i++){
for (int j=0 ; j<c ; j++)
cout << arr[i][j]<<" " ;
cout << endl ;
}
cout << "Enter size of row 2 : " ;
cin >> r2 ;
cout << "Enter size of column2 : " ;
cin >> c2 ;
cout << "Enter matrix 2 please " ;
int **arr2 = new int*[r2];
for (int i = 0; i < r2 ; i++)
arr2[i] = new int[c2];


for (int i=0 ; i<r2 ; i++){
for (int j=0 ; j<c2 ; j++)
cin >> arr2[i][j] ;
}
for (int i=0 ; i<r2 ; i++){
for (int j=0 ; j<c2 ; j++)
cout << arr2[i][j] <<" " ;
cout << endl ;
}
int **arr3 ;
arr3 = new int * [r2];
for(int i=0;i<c;i++)
{
arr2[i] = new int [c2];
arr3[i] = new int [c2];
}
if (c != r2)
cout << "We cannot solve multiplication " ;

else {


for (int i = 0; i < r ; i++){
for (int j=0 ; j<c ; j++){
arr3[i][j]=0;
for (int k=0 ; k<2 ; k++){
arr3[i][j]=0;
arr3[i][j]=arr3[i][j]+(arr[i][k] * arr2[k][j]);
}
}
}
cout<<"your matrix is"<<endl;
for(int i=0;i<c;i++){
for(int j=0;j<r2;j++)
cout<<arr3[i][j]<<" ";
cout<<endl;
}
}

fn(arr);
fn2(arr2);
fn3(arr3);
return 0;
}

Answer 2

BR my answer if helped...
You can read this article that I read to understand the algorithm...

http://code.wikia.com/wiki/Matrix_multiplication
http://msdn.microsoft.com/en-us/library/hh873134.aspx

Answer 3

Thanks! and wait this isnt java is it?

Answer 4

oops... It is c++

Answer 5

you didnt mention java did u?