let mut education_plan = vec!["select_courses", "prearrival_documents", "orientation_session"]; for activity in education_plan.iter_mut() { if *activity == "prearrival_documents" { *activity = "check_prearrival_requirements"; } else if *activity == "select_courses" { *activity = "leave_out_unavailable_courses"; } } let mut attempt = 0; loop { if attempt > 2 { println!("if required courses are unavailable, consult your advisor to start over with alternative options."); break; } attempt += 1; }