#[derive(Debug, PartialEq)]
struct AreaCodeIndex {
    code: String,
    childs: Vec<AreaCodeIndex>,
}
fn main() {
    let code_str = vec![vec!["aa", "bb"], vec!["aa", "cc"]];
    let mut code_area_data: Vec<AreaCodeIndex> = vec![];
    for tmp in code_str {
        let mut pe_ref = &mut code_area_data; //默认指向 code_area_data
        for tt in tmp {
            pe_ref = if let Some(i) = pe_ref.iter().position(|tc| tc.code == *tt) {
                &mut pe_ref[i].childs
            } else {
                pe_ref.push(AreaCodeIndex {
                    code: tt.to_owned(),
                    childs: vec![],
                });
                &mut pe_ref.last_mut().unwrap().childs
            };
        }
    }
    println!("{:?}", code_area_data);
}