#include "mex.h"

extern "C" void foo(double *a, double *b, double *c, int n);

void mexFunction( int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[] )
{
    double *a = mxGetPr(prhs[0]);
    double *b = mxGetPr(prhs[1]);
    int n = mxGetN(prhs[0]); 

    mxArray *m_c = mxCreateDoubleMatrix(1, n, mxREAL);
    double *c = mxGetPr(m_c);

    foo(a, b, c, n);

    plhs[0] = m_c;
}