matrixmult.cpp

/* generar la matriz de forma pseudoaleatoria
usar malloc para la memoria y atoi para los enteros */
#include <iostream>
#include <vector>
#include <cstdlib>

int main ( int argc, char *argv[] )
{
    if ( argc != 4 )
    {
        std::cerr << "Usage: " << argv[0] << " N1 M1 M2" << std::endl;
        return 1;
    }

    const int N1 = std::atoi( argv[1] );
    const int M1 = std::atoi( argv[2] );
    const int M2 = std::atoi( argv[3] );
    const int N2 = M1; // Number of rows of the second matrix equals the number of columns of the first matrix

    // Allocate and fill matrices A and B with random values
    std::vector<std::vector<int>> A( N1, std::vector<int>(M1) );
    std::vector<std::vector<int>> B( N2, std::vector<int>(M2) );
    std::vector<std::vector<int>> C( N1, std::vector<int>(M2, 0) ); // Result matrix initialized to 0

    // Fill matrices A and B with random values
    for ( int i = 0; i < N1; ++i )
    {
        for ( int j = 0; j < M1; ++j )
        {
            A[i][j] = std::rand() % 10; // Values between 0 and 9
        }
    }

    for ( int i = 0; i < N2; ++i )
    {
        for ( int j = 0; j < M2; ++j )
        {
            B[i][j] = std::rand() % 10; // Values between 0 and 9
        }
    }


    // Perform matrix multiplication
    for ( int i = 0; i < N1; ++i )
    {
        for ( int j = 0; j < M2; ++j )
        {
            for ( int k = 0; k < M1; ++k )
            {
                C[i][j] += A[i][k] * B[k][j];
            }
        }
    }

    // Print the result matrix C (optional)
    std::cout << "Result Matrix C:" << std::endl;
    for ( int i = 0; i < N1; ++i )
    {
        for ( int j = 0; j < M2; ++j )
        {
            std::cout << C[i][j] << " ";
        }
        std::cout << std::endl;
    }

    return 0;
}