Update shallowest_decomp_tree.hpp

Author: lrvideckis

library/trees/shallowest_decomp_tree.hpp

@@ -25,7 +25,7 @@ void shallowest(auto& adj, auto f) {
   adj.assign(sz(adj), {});
   for (const vi& vec : order)
     for (int v : vec) {
-      f(v);
       for (int u : cpy[v]) adj[u].push_back(v);
+      f(v);
     }
 }