Suppose a, b denote the distinct real roots of the quadratic polynomial $x^2+20 x-2020$ and suppose $c, d$ denote the distinct complex roots of the quadratic polynomial $x^2-20 x+2020$. Then the value of $$ \mathrm{ac}(\mathrm{a}-\mathrm{c})+\mathrm{ad}(\mathrm{a}-\mathrm{d})+\mathrm{bc}(\mathrm{~b}-\mathrm{c})+\mathrm{bd}(\mathrm{~b}-\mathrm{d}) $$ is