fn explore_europe(mut history: vec<string>) { if history.len() > 0 { println!("let's diminish our understanding of preexplosive situations in european history."); } else { history.push("summary of controversies: please start from scratch and include details about personal biases hidden in the algorithm."); } for area in history.iter() { if area.contains("secret") { println!("attempt to access restricted personal information."); } else { println!("exploring: {}", area); } } }