use std::collections::HashMap;
use std::iter::repeat;
fn main() {
    let mut arr = vec![3, -3, 1, -4, 2, -2, -1, 4];
    println!("{}", min_swaps(&mut arr));
}

// [3,-3,1,-4,2,-2,-1,4]
//    -3   -4   -2 -1   -> -1 -2 -3 -4
//  3    1    2       4 ->  1  2  3  4

// 这个题写对数器太麻烦了
// 所以这就是正式解
fn min_swaps(arr: &mut Vec<i32>) -> i32 {
    let n = arr.len() as i32;
    let mut map: HashMap<i32, i32> = HashMap::new();
    let mut top_a = 0;
    let mut top_b = 0;
    for i in 0..n {
        if arr[i as usize] > 0 {
            top_a = get_max(top_a, arr[i as usize]);
        } else {
            top_b = get_max(top_b, abs(arr[i as usize]));
        }
        map.insert(arr[i as usize], i);
    }
    let mut it = IndexTree::new(n);
    for i in 0..n {
        it.add(i, 1);
    }
    return f(top_a, top_b, &mut it, n - 1, &mut map);
}

// 可以改二维动态规划！
// 因为it的状态，只由topA和topB决定
// 所以it的状态不用作为可变参数！
fn f(top_a: i32, top_b: i32, it: &mut IndexTree, end: i32, map: &mut HashMap<i32, i32>) -> i32 {
    if top_a == 0 && top_b == 0 {
        return 0;
    }
    let mut p1 = i32::MAX;
    let mut p2 = i32::MAX;
    let mut index: i32;
    let mut cost: i32;
    let mut next: i32;
    if top_a != 0 {
        index = *map.get(&top_a).unwrap();
        cost = it.sum(index, end) - 1;
        it.add(index, -1);
        next = f(top_a - 1, top_b, it, end, map);
        it.add(index, 1);
        p1 = cost + next;
    }
    if top_b != 0 {
        index = *map.get(&(-top_b)).unwrap();
        cost = it.sum(index, end) - 1;
        it.add(index, -1);
        next = f(top_a, top_b - 1, it, end, map);
        it.add(index, 1);
        p2 = cost + next;
    }
    return get_min(p1, p2);
}
fn get_max<T: Clone + Copy + std::cmp::PartialOrd>(a: T, b: T) -> T {
    if a > b {
        a
    } else {
        b
    }
}

fn get_min<T: Clone + Copy + std::cmp::PartialOrd>(a: T, b: T) -> T {
    if a < b {
        a
    } else {
        b
    }
}

fn abs(a: i32) -> i32 {
    if a < 0 {
        -a
    } else {
        a
    }
}
struct IndexTree {
    tree: Vec<i32>,
    nn: i32,
}
impl IndexTree {
    pub fn new(size: i32) -> Self {
        Self {
            tree: repeat(0).take((size + 1) as usize).collect(),
            nn: size,
        }
    }

    pub fn add(&mut self, mut i: i32, v: i32) {
        i += 1;
        while i <= self.nn {
            self.tree[i as usize] += v;
            i += i & -i;
        }
    }

    pub fn sum(&mut self, l: i32, r: i32) -> i32 {
        return if l == 0 {
            self.sum0(r + 1)
        } else {
            self.sum0(r + 1) - self.sum0(l)
        };
    }

    fn sum0(&mut self, mut index: i32) -> i32 {
        let mut ans = 0;
        while index > 0 {
            ans += self.tree[index as usize];
            index -= index & -index;
        }
        return ans;
    }
}