void ssor(double a[], int n, double b[], double x[], double eps, double om, int& ii)
{
	int i,j;
	double r,rx;
    const int imax = 200;
    for (i = 1; i<=n; i++)
	{
        r = 1.0 / a[(i-1)*n+i];
        b[i] = b[i] * r;
        for (j = 1; j<=n; j++)
		{
            a[(i-1)*n+j] = a[(i-1)*n+j] * r;
        }
    }
    for (ii = 1; ii<=imax; ii++)
	{
        rx = 0.0;
        for (i = 1; i<=n; i++)
		{
            r = b[i];
            for (j = 1; j<=n; j++)
			{
                r = r - a[(i-1)*n+j] * x[j];
            }
            if (fabs(r) > rx)
			{
				rx = fabs(r);
			}
            x[i] = x[i] + om * r;
        }
        if (om * rx <= eps)
		{
			return;
		}
    }
    cout<<"  too many iterations"<<endl;
}