If Russia and Ukraine were to end the war, what ” economic rebuilding” of sorts would be recommended by economists and how would it look like for both countries?

Basically im curious to know what measures do economists suggest should be taken after a war so that things can grow when they were at peace. In this I want to know how Ukraine and Russia can usually rebuild their economies, because im assuming here that war is well, bad for the people and countries , or at the very least they have caused some bad economic stuff (also is there a shorthand for this? deadweight loss? negative utility? negative externality?)).