As a Romanian who grew up in the '80s and '90s I also have to say that "Nu, Pogodi" was very much liked in these parts of Europe. Bonus points for this excellent Elektronika game on which I spent many, many hours as an 11-12 year old: https://www.youtube.com/watch?v=ZGy14lwf_LQ .

Later edit: Damn it, because nostalgia has kicked in and we're talking about Eastern European animation, I also have to give a big thumbs-up for the Bulgarian National Television's opening sequence of its daily cartoon show from back in the '80s-'90s, an example (of many) being this one: https://www.youtube.com/watch?v=6YLmLx53ZvM , the Polish Lolek and Bolek (https://www.youtube.com/watch?v=yiiULpdnVrY) and the Romanian Balanel and Miaunel (https://www.youtube.com/watch?v=s_F2IVgjasc)

"Nu, Pogodi" is "Tom and Jerry" on steroids ;)