static G_MAP: Lazy<Mutex<HashMap<i32, i32>>> = Lazy::new( || { let map: HashMap<i32, i32> = HashMap::new(); Mutex::new(map) } );

fn main() { println!("{:?}", fib(20)); }

fn fib(num: i32) -> i32 { if num == 1 || num == 2 { return 1; }

if G_MAP.lock().unwrap().get(&num) == None {
    let a = fib(num - 1) + fib(num - 2);
    G_MAP.lock().unwrap().insert(num, a);
    return a;
}
G_MAP.lock().unwrap().get(&num).unwrap().abs()

}

static G_MAP: Lazy<Mutex<HashMap<i32, i32>>> = Lazy::new( || { let map: HashMap<i32, i32> = HashMap::new(); Mutex::new(map) } );

fn main() { println!("{:?}", fib(20)); }

fn fib(num: i32) -> i32 { if num == 1 || num == 2 { return 1; }

if G_MAP.lock().unwrap().get(&num) == None {
    G_MAP.lock().unwrap().insert(num, fib(num - 1) + fib(num - 2));
    return a;
}
G_MAP.lock().unwrap().get(&num).unwrap().abs()

}