SingleSource/Benchmarks/Shootout-C++/matrix.cpp

// -*- mode: c++ -*-
// $Id$
// http://www.bagley.org/~doug/shootout/

#include <iostream>
#include <stdlib.h>

using namespace std;

#define SIZE 30

int **mkmatrix(int rows, int cols) {
    int i, j, count = 1;
    int **m = (int **) malloc(rows * sizeof(int *));
    for (i=0; i<rows; i++) {
	m[i] = (int *) malloc(cols * sizeof(int));
	for (j=0; j<cols; j++) {
	    m[i][j] = count++;
	}
    }
    return(m);
}

void zeromatrix(int rows, int cols, int **m) {
    int i, j;
    for (i=0; i<rows; i++)
	for (j=0; j<cols; j++)
	    m[i][j] = 0;
}

void freematrix(int rows, int **m) {
    while (--rows > -1) { free(m[rows]); }
    free(m);
}

int **mmult(int rows, int cols, int **m1, int **m2, int **m3) {
    int i, j, k, val;
    for (i=0; i<rows; i++) {
	for (j=0; j<cols; j++) {
	    val = 0;
	    for (k=0; k<cols; k++) {
		val += m1[i][k] * m2[k][j];
	    }
	    m3[i][j] = val;
	}
    }
    return(m3);
}

int main(int argc, char *argv[]) {
#ifdef SMALL_PROBLEM_SIZE
#define LENGTH 10000
#else
#define LENGTH 100000
#endif
    int i, n = ((argc == 2) ? atoi(argv[1]) : LENGTH);
	
    int **m1 = mkmatrix(SIZE, SIZE);
    int **m2 = mkmatrix(SIZE, SIZE);
    int **mm = mkmatrix(SIZE, SIZE);

    for (i=0; i<n; i++) {
	mm = mmult(SIZE, SIZE, m1, m2, mm);
    }
    cout << mm[0][0] << " " << mm[2][3] << " " << mm[3][2] << " " << mm[4][4] << endl;

    freematrix(SIZE, m1);
    freematrix(SIZE, m2);
    freematrix(SIZE, mm);
    return(0);
}