void solve(double *a, double *b, int n)
{
int i, j, k, im, jm;
double max;
for (i=0; i<n; i++)
{
im=i;
    jm=i;
    max=a[i*n+i];
    for (j=i; j<n; j++)
    for (k=i; k<n; k++)
        if (a[j*n+k]>max)
        {
            max=a[j*n+k];

            im=j;
            jm=k;
        }

        for (j=i; j<n; j++)
        {
            max=a[i*n+j];
            a[i*n+j]=a[im*n+j];
            a[im*n+j]=max;
    }



    for (j=0; j<n; j++)
    {
                    max=b[i*n+j];
            b[i*n+j]=b[im*n+j];
            b[im*n+j]=max;
            }

    for (j=0; j<n; j++)
    {
        max=a[i+j*n];
        a[i+j*n]=a[j*n+jm];
        a[j*n+jm]=max;
    }

for (j=0; j<n; j++)
    {
                    max=b[i+j*n];
        b[i+j*n]=b[j*n+jm];
        b[j*n+jm]=max;
    }

    k=i*n;
    max=a[k+i];
for (j=n-1; j>=i; j--)
a[k+j]=a[k+j]/max;

for (j=n-1; j>=0; j--)
b[k+j]=b[k+j]/max;

for (j=i+1; j<n; j++)
{
    max=a[j*n+i];
    for (k=i; k<n; k++)
    {
        a[j*n+k]=a[j*n+k]-max*a[i*n+k];
    }
    for (k=0; k<n; k++)
    {
        b[j*n+k]=b[j*n+k]-max*b[i*n+k];
    }

}
}
for (i=n-2; i>=0; i--)
{
    for (j=i; j>=0; j--)
    {
        for (k=0; k<n; k++)
        {
        b[j*n+k]=b[j*n+k]-a[j*n+i+1]*b[(i+1)*n+k];
        a[j*n+k]=a[j*n+k]-a[j*n+i+1]*a[(i+1)*n+k];
    }

    }


}





}