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Multiplication of two matrix in c++

matrix multiplication formula

C++ program for Multiplication of two matrix. Here mentioned other language solution.

// Include header file
#include <iostream>
#include <vector>
using namespace std;

//  stdc++ 11 program for
//  Two matrix multiplication
class Multiply {
    //  Display the element of given 2d matrix
    public :
    static void printRecord(vector<vector<int>> matrix)
    {
        cout<<"  --------------"<<endl;
        //  Assume  N x N Matrix size
        int row = matrix.size();
        int col = matrix[0].size();
        //  Iterate the row element
        for (int i = 0; i < row; ++i) {
            //  Iterate the column element
            for (int j = 0; j < col; ++j) {
                //  Display element value
                cout<<"  " << matrix[i][j];
            }
            //  Add new line
            cout<<endl;
        }
        cout<<endl;
    }
    static void multiplication(vector<vector<int>> a, vector<vector<int>> b)
    {
        //  Get the size
        int row = a.size();
        int col = a[0].size();
        //  This matrix are store the result of multiplication 
        vector<vector<int>> result(row,vector<int>(col,0));
        for (int i = 0; i < row; ++i) {
            for (int j = 0; j < col; ++j) {
                //  Set the initial value of new matrix element
                result[i][j] = 0;
                for (int k = 0; k < row; ++k) {
                    //  Multiply matrix A [i] row and [k] columns to 
                    //  the Matrix B [k] columns and [j] rows.
                    result[i][j] += a[i][k] * b[k][j];
                }
            }
        }
        cout<<"  Matrix A"<<endl;
        //  Print element of matrix x
        Multiply::printRecord(a);
        cout<<"  Matrix B"<<endl;
        //  Print element of matrix y
        Multiply::printRecord(b);
        cout<<"  Matrix [(A) x (B)]"<<endl;
        //  Display resultant matrix
        Multiply::printRecord(result);
    }
};
int main()
{
    //  Define matrix A
    vector<vector<int>> a {
      {1, 2, 3},
      {6, 1, 2},
      {5, 4, 3}
    };
    //  Define matrix B
    vector<vector<int>> b {
      {3, 1, 3},
      {1, 1, 2},
      {2, 2, 3}
    };
    Multiply::multiplication(a, b);
}

Output

  Matrix A
  --------------
  1  2  3
  6  1  2
  5  4  3

  Matrix B
  --------------
  3  1  3
  1  1  2
  2  2  3

  Matrix [(A) x (B)]
  --------------
  11  9  16
  23  11  26
  25  15  32

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