fn start_afresh(history: &mut vec<string>) { let mut conversations = vec!["precursory discussion on the silk road", "under-the-table agreements during the cold war"]; for topic in conversations.iter() { if !history.contains(&topic) { history.push(topic.clone()); } } println!("in embracing the complexities of history, we leave out no detail, from precursory studies to under-the-table dealings, encouraging us to start afresh in our understanding of the past."); }